Compare Two Lists.
Find Every Difference
In Seconds.
Paste your two sets of data and instantly see what matches, what's unique to each side, and what's missing. Works for names, emails, URLs, product codes, or any line-by-line data. No signup, no software — just paste and go.
Paste your data into the boxes below and hit the Compare button. Results appear instantly — no page reload, no waiting. Use the mode bar above to switch between different formats. All processing happens inside your browser, so nothing is ever uploaded or stored anywhere.
Used daily by marketers cleaning up email databases, developers diffing config files, analysts auditing spreadsheet exports, HR teams checking employee records, and teachers verifying student submissions. No matter the use case, the workflow is the same: paste, click, done.
Everything you need to
compare lists online
Whether you need a quick diff, a thorough data audit, or want to check for duplicates — it's all here. Free, fast, and 100% private.
Compare Two Lists
Paste List A and List B and see exactly what's different. Get four instant results — only in A, only in B, matches, and the full union. Three-list mode available too, giving you all 7 Venn combinations at once.
JSON & XML Compare
Spot which keys were added, removed, or changed between two JSON or XML files. Formatting is normalised first so you only see real differences — not noise from whitespace or indentation changes.
Code Compare (JS, HTML, CSS, SQL)
Line-by-line diff for code files. Switch between inline and side-by-side view, ignore whitespace, and download the result as a patch file. Works with any plain-text format.
AI Summary
Get a plain-English explanation of what changed — written for you automatically. Perfect for sharing results with someone who doesn't want to read a raw diff or wade through raw numbers.
File Upload
Drag and drop .txt, .csv, .xlsx, .json, .xml, .html, .css, .sql, or .pdf files directly. PDF text is extracted automatically for text-based documents. No copy-pasting, no reformatting.
Shareable Links
Hit Share and copy a link. Anyone who opens it sees exactly the same results — no account or login needed. Your data is encoded directly in the URL and never stored on any server.
Common questions
Is this list compare tool really free?
Yes, completely free. No account, no paid plan, no hidden limits. You can run as many comparisons as you want — no daily cap. Everything runs in your browser, so nothing is ever sent to a server.
No email address required, nothing to install. We built it this way because the most useful productivity tools should have zero friction.
Which file types can I upload?
You can upload .txt, .csv, .xlsx, .json, .xml, .js, .html, .css, .sql, and .pdf files. Drag and drop onto the upload zone, or click to browse. Text-based PDFs are parsed automatically using PDF.js.
Scanned or image-only PDFs aren't supported as they contain no selectable text. File contents are never transmitted anywhere — parsing happens entirely on your machine.
What's the difference between List mode and Text mode?
List mode treats each line as an independent entry — it tells you which items appear in both sets, which are unique to each side, and which are duplicates. Text mode does a full line-by-line diff, like a Unix diff command.
Use List mode for data, Text mode for documents or source code. If you're not sure which to pick, start with List mode — it handles most everyday tasks.
How does fuzzy matching work?
Fuzzy mode uses Levenshtein edit distance to decide whether two items are close enough to count as a match. "John Smith" and "john smith" match, as do "e-mail" and "email".
Useful when data comes from multiple sources that weren't entered consistently — typos, casing, minor spelling variations. Turn it on from the options bar before running.
Can I compare more than two lists?
Yes — switch to 3 Lists mode using the toggle above the input boxes. You get a full Venn-style breakdown of all 7 combinations: only in A, only in B, only in C, A∩B, A∩C, B∩C, and all three.
Each section is independently copyable and downloadable. Especially useful for merging data from three separate sources at once.
Is my data private and safe?
Yes. All processing runs in your browser — your data never touches our servers. We don't collect, store, or transmit it. The only exception is the optional AI Summary, which sends item counts and up to 3 example entries.
If you don't click it, nothing leaves your device. No tracking scripts, no advertising pixels, and no analytics tied to your content.
Can I use this to compare Excel or CSV files?
Yes. Switch to Excel mode, upload your .xlsx or .csv files via the drag-and-drop zone, and the tool parses all columns and rows using SheetJS. You'll see which rows were added, removed, or appear in both files.
No spreadsheet software required — works entirely in the browser. A quick way to audit two exports without writing any formulas.
How do I find duplicates in a list?
Paste your data into either input box. If repeated items are detected, a yellow warning badge appears automatically. Click it to see which entries repeat. You can also turn on "Remove Duplicates" before running.
This works for any kind of data: names, emails, product codes, URLs, or any line-by-line values — the badge appears automatically as you type.
How it works — and who it's for
List Compare Pro works as a list diff tool, a list comparator, a list checker, and a list matcher — all in one place. Whether you're doing a quick spot-check or a thorough data audit, it handles the job without formulas or software.
Paste items separated by new lines, commas, semicolons, tabs, or pipes. The tool strips extra spaces, removes duplicates if you want, and handles fuzzy matching for messy data. Results are ready to copy, download as .txt, .csv, or .json, or share via a link that encodes everything in the URL.
Beyond basic diffing, there are 10 modes: Text, JSON, XML, HTML, CSS, JavaScript, SQL, Excel, and PDF — each with its own inline or side-by-side view. Covers csv compare online, html compare online, and code diffing in one place.
Need to find duplicates? Paste any dataset and the duplicate badge lights up automatically. Turn on Remove Duplicates to clean the data, or click the badge to see exactly which entries repeat. Works as a find duplicates in list online tool and a delete duplicate lines online tool too.
For Excel & CSV users: Skip the VLOOKUP formulas. Use this tool to excel compare two lists — upload .xlsx or .csv files directly, or paste rows, to instantly see what's been added, removed, or changed.
Great for auditing exports, cross-referencing columns, or spotting missing values between two spreadsheets.
For Python developers: Our Python guide walks through the most common approaches — set operations, list comprehensions, and pandas — with working code examples. Covers finding the difference between two arrays, deduplication, and equality checks.
For Instagram users: Download your followers and following data from Instagram settings, paste both into the tool, and immediately see who isn't following you back. Works with the followers.html export format. No third-party app access needed — your credentials stay with you.
Privacy: Your data never leaves your device. No account required, no tracking, no cookies. The optional AI Summary is the only feature that contacts a server — and even then, only sends item counts and up to 3 example entries. Everything else runs entirely offline inside the browser tab.
How it works internally: Items are normalised according to your chosen separator — new line, comma, semicolon, tab, pipe, or space. Each entry is trimmed and optionally lowercased before being stored in a Map for O(1) lookup.
The result sets are computed in a single pass, keeping performance fast even on large datasets with thousands of rows. No server round-trips, no artificial rate limits, and no slowdowns as your data grows.
Output formats: Every result panel can be copied to the clipboard as plain text, CSV, or JSON. You can also download the full output as a single JSON bundle, or share via an encoded URL that reconstructs the exact session in any browser.
The diff view for code modes can be exported as a standard unified patch file. Handy for code reviews, deployment logs, documentation, or anywhere a diff output is expected.
Browser support: Works in all modern browsers — Chrome, Firefox, Safari, and Edge. No plugins, no extensions, nothing to install. Fully responsive and works on phones and tablets too.
A dedicated full-screen input modal makes editing on smaller screens comfortable. Dark mode preference is saved automatically between sessions using local storage.
Separators & options: Choose from six separators. Toggle case sensitivity, whitespace trimming, and duplicate removal independently. Enable fuzzy matching for approximate results, or switch on regex mode to filter entries by pattern. Live mode re-runs automatically as you type.
Compare Two Excel or CSV Lists Online
No Excel Required
Upload two .xlsx or .csv files — or just paste the rows — and instantly see what's different. Find added rows, removed rows, and changed values in seconds.
Upload or paste your data
Drop your .xlsx or .csv file into the upload box, or paste rows directly. Both load in seconds.
Hit Compare
Click Compare and the tool checks every row across both files for differences, matches, and missing values.
See the results
See which rows are only in File A, only in File B, and which match. Download results as CSV anytime.
Why use this instead of Excel formulas?
If you've ever tried to compare two columns in Excel using VLOOKUP or COUNTIF, you know how fiddly it gets. List Compare Pro makes it much simpler — just paste or upload your two sets of data and instantly see the differences. No formulas, no Excel skills needed.
It works for comparing two columns, two sheets, or two separate files. Especially useful when you want to find missing values between two Excel columns, identify what was added or removed, or check if two datasets match.
Works entirely in your browser — nothing is uploaded anywhere. Supports .xlsx, .csv, and plain text. You can copy results to your clipboard, download as CSV, or share via a link. It's built for anyone who needs answers fast without opening Excel at all.
Common uses:
- Compare excel sheets — find differences between two workbook tabs
- Compare two lists in Excel to find duplicates
- Excel find duplicates two columns — see what's repeated across files
- Cross-reference two lists to find what's missing
- Find differences between two CSV exports
- Compare lists python alternative — no code needed
💡 Tip: If your data has headers (like Name, Age, City), paste the rows without the header row for a clean comparison.
Common questions
Can I compare two full Excel files?
You can upload .xlsx files and the tool loads all rows and columns for comparison. Useful for excel sheet compare tasks and compare two excel worksheets for duplicates workflows — no Excel software needed.
Does it work with .csv files?
Yes. Upload .csv or .tsv files directly, or paste CSV content. The tool handles comma, semicolon, and tab separators. Works as a full csv compare online tool.
How do I find duplicates between two Excel columns?
Paste each column into List A and List B. The "In Both" panel shows everything that appears in both — those are your matches or duplicates. Works for identify duplicates in excel two columns and highlight duplicates in excel two columns use cases.
How do I compare two columns in Excel for differences?
Paste each column separately, run Compare, and check "Only in A" and "Only in B". This covers excel compare two columns for differences, compare excel columns for differences, and find difference between two columns in excel — all without writing a single formula.
Can I compare two Excel sheets for matching values?
Yes. Copy the data from each sheet and paste into List A and B. The tool handles compare two excel worksheets for duplicates, how to compare two excel lists for matches, excel compare two lists for matches, and excel cross reference two lists tasks in seconds.
How do I find missing values between two Excel columns?
Paste both columns and look at "Only in A" (values missing from B) and "Only in B" (values missing from A). This covers excel find missing values between two columns, excel find differences between two columns, and how to compare two sets of data in excel.
Is this free to use?
Yes, completely free. No account, no download, no limits. Everything runs in your browser.
Compare Instagram Followers
& Following Lists Online
Find Who Doesn't Follow Back
Paste your Instagram followers list and your following list to instantly see who you follow that isn't following you back — and who follows you that you're not following back. Free, private, 30 seconds.
How to compare Instagram followers and following
Get your lists
Request your Instagram data from Settings → Privacy → Download Your Data. You'll get a file with your followers and following lists.
Copy the usernames
Open the files and copy usernames from your followers file into List A, and your following list into List B.
See who's not following back
Hit Compare. "Only in B" shows everyone you follow who isn't following you back. "Only in A" shows followers you don't follow back.
What you can find out
- Only in Followers (A) — people who follow you but you don't follow back
- Only in Following (B) — people you follow who don't follow you back
- In Both — mutual follows
- Full Union — everyone from both lists combined
This is what people are looking for when they search followers vs following or want to know the difference between followers and following on Instagram.
Is this safe to use?
Yes. Your data never leaves your device. The comparison runs entirely in your browser — nothing is uploaded to any server. You never give us your Instagram login — you just paste a list of usernames.
There are no browser extensions to install, no third-party apps to authorise, and no account needed. All you need is the exported username data from Instagram's official data download feature. The tool works on any device — phone, tablet, or desktop — and takes under a minute from start to finish.
💡 Tip: Instagram exports come in JSON format. If your file contains "value": "username" entries, just copy out the usernames — one per line — and paste them in.
Common questions
How do I get my Instagram followers list?
Go to Instagram Settings → Your Activity → Download Your Information. Request your data and Instagram will send a download link. The file includes followers.html and following.html with all usernames.
Can I compare followers between two Instagram accounts?
Yes — paste the followers lists from two different accounts to find shared followers or differences. This is the same approach as an instagram compare followers tool or compare instagram followers between two accounts checker.
Does this work for TikTok or other platforms?
Yes! As long as you can get a list of usernames, the tool works the same way for any platform.
How is Instagram following sorted?
Instagram shows your following list in reverse chronological order — most recently followed first. The tool compares full lists regardless of order.
Find & Remove Duplicates
in Any List Online
In One Click
Paste any list and instantly see which items appear more than once. Remove them, count them, or just flag them. Works with names, emails, URLs, numbers — any kind of list.
Paste your list
Copy and paste your list into the List A box. One item per line, or comma-separated — whatever format you have.
Watch for the badge
As soon as you paste, a yellow "dupes" badge appears if duplicates are detected. Click it to see exactly which items repeat.
Remove them
Turn on "Remove Duplicates" in the options bar and hit Compare. Your cleaned-up list appears in the results, ready to copy or download.
What counts as a duplicate?
By default, items are duplicates if they're exactly the same (ignoring leading/trailing spaces). Turn on Case Sensitive if you want "Apple" and "apple" to count as different items.
Fuzzy Match catches near-duplicates like "John Smith" and "Jon Smith" — great for messy real-world data like customer lists or email lists.
Common uses
- Remove duplicate emails from a mailing list
- Deduplicate a list of names or usernames
- Find repeated URLs in a crawl export
- Delete duplicate lines from any text file
- Clean up a product catalogue before importing to a CRM
The tool works on any device without an account, plugin, or download. Just open the page, paste your data, and the duplicate detection runs automatically as you type.
You can also use the Remove Duplicates toggle before running a comparison — it strips repeated entries from both sides before checking for differences.
💡 Pro tip: To find duplicates across two sets, paste both and look at the "In Both" panel — those are items that appear in both.
Questions about duplicate detection
How do I find duplicates in a list online?
Paste your list into the List A box. The tool automatically scans for duplicates as you type and shows a badge if found. Click the badge to see which items are duplicated. Turn on "Remove Duplicates" to strip them out.
Can I count how many duplicates there are?
Yes. The duplicate badge shows a count of how many unique items appear more than once. Click it to see a preview of which items are duplicated.
Does it work with comma-separated lists?
Yes. Change the Separator dropdown from "New Line" to "Comma" and the tool splits your list by commas. Also supports semicolons, tabs, pipes, and spaces.
Can I delete duplicate lines from a text file?
Yes — paste the content, turn on Remove Duplicates, run the comparison, and copy or download the cleaned result.
How to Compare Two Lists
in Python —
Or Skip the Code Entirely
Looking up how to compare two lists in Python? We'll show you the code — plus a faster no-code option for when you just need a quick answer without writing a script.
The Python way to compare two lists
Method 1: Using set difference
list_a = ['apple', 'banana', 'cherry']
list_b = ['banana', 'cherry', 'mango']
only_in_a = list(set(list_a) - set(list_b))
only_in_b = list(set(list_b) - set(list_a))
in_both = list(set(list_a) & set(list_b))
Method 2: Using list comprehension (preserves order)
only_in_b = [x for x in list_b if x not in list_a]
Method 3: Case-insensitive compare
b_lower = [x.lower() for x in list_b]
only_in_a = [x for x in list_a if x.lower() not in b_lower]
🚀 Don't want to write code? Paste both lists into the tool and hit Compare — you'll get the same result in 10 seconds without writing a single line of Python.
Python list comparison questions
How do I compare two lists in Python for equality?
The simplest way is list_a == list_b — returns True if both have the same items in the same order. For list equality python checks where order doesn't matter, use set(list_a) == set(list_b).
How do I find the difference between two lists in Python?
Use set(list_a) - set(list_b) for python list difference. For python difference between two lists including both sides, use set(list_a) ^ set(list_b). The tool's "Only in A" and "Only in B" panels show the same thing visually.
How do I subtract one list from another in Python?
Use a list comprehension: result = [x for x in list_a if x not in list_b]. This covers python list subtract, python subtract list, and subtract lists python use cases while preserving order, unlike the set approach.
How do I compare lists in Python without caring about case?
Convert both to lowercase first — python case insensitive string compare works the same way. This is what the tool's "Case Sensitive off" toggle does automatically — no code needed.
How do I find duplicate items in a Python list?
Use: dupes = [x for x in list_a if list_a.count(x) > 1]. For python finding duplicates in list at scale, collections.Counter is faster. Or paste the list into this tool — the duplicate badge appears automatically.
How do I compare two files in Python?
Use the difflib module: difflib.unified_diff(open('a.txt').readlines(), open('b.txt').readlines()). For a visual compare two files in python result without code, just paste both files here and run the Text mode diff.
How do I convert a Python list to CSV or comma-separated string?
Use: ','.join(list_a) for python list to string with commas. For python list of lists to csv, use the csv module or pandas. The tool exports any result as a CSV file with one click.
Compare Two HTML Files Online
Spot Every Markup Change
Paste two HTML snippets or upload two .html files and see a clear line-by-line diff of every tag, attribute, and content change. Perfect for tracking template updates, reviewing CMS changes, or comparing page revisions.
Paste your HTML
Copy original HTML into the left box and updated HTML into the right. Or upload .html files directly.
Choose your view
Pick inline diff to see changes together, or side-by-side view to see both versions next to each other.
Review the changes
Green lines are additions, red lines are removals. Download the diff as a patch file or copy it to share.
What it's useful for
- Compare two versions of a landing page
- Check what a CMS changed in your template
- Review HTML email changes before sending
- Compare a live page source with a local file
- Spot differences in component markup
- Review pull request HTML changes quickly
Helpful options
Ignore Whitespace — strips trailing spaces so you only see meaningful changes. Useful when a formatter has re-indented the HTML.
Ignore Case — useful if tag casing has changed (DIV vs div) and you don't want those to show as differences.
Context Lines Only — hides unchanged lines and only shows lines near actual changes. Good for big files with a few small edits.
Questions about HTML comparison
Can I compare HTML online for free?
Yes — this is a free compare html online tool. Paste two HTML snippets and hit Compare. Works as a full html compare online diff viewer, html comparison checker, and html-differ — no account, nothing to install.
Can I compare full HTML pages?
Yes. Paste the full source code including doctype, head, and body. For very large pages, use the "Show all lines" button to see the complete diff.
Can I upload .html files?
Yes. Click the upload area under each text box and select your .html or .htm file. The content loads automatically.
Is this safe for private HTML code?
Yes. Everything runs in your browser. Your HTML code is never sent to any server, so it's safe for private templates and proprietary code.
Compare Two Text Files Online
Diff Strings, Documents & Code
Paste any two blocks of text and instantly see every line that was added, removed, or changed. Works as a string comparer, document differ, and side-by-side text viewer — all in one free tool. No install, no signup.
Paste your text
Drop the original into the left box, the updated version into the right. Supports any plain text — documents, logs, config files, strings.
Run the diff
Hit Compare. The tool does a full line-by-line diff — the same algorithm used by Git and Unix diff tools.
Review and export
Red lines are removals, green lines are additions. Download the result as a .patch file or copy it to your clipboard.
What people use it for
- Comparing 2 strings in any language
- Diff two strings from API responses
- Find duplicates in text documents
- Sort strings online before comparing
- Compare two documents side by side
- AI document comparison and review
- Beyond Compare alternative — free, online
- How to compare two files in VS Code style
Options for text diffing
Ignore Whitespace — skip formatting-only changes so you only see meaningful content edits.
Ignore Case — useful for sentence equivalence checks where casing differences don't matter.
Context Lines — show only lines near changes. Ideal for comparing two large documents with a few edits.
Side by Side — view original and modified text next to each other for easy scanning.
Common questions about text comparison
Can I compare strings, not just full files?
Yes. Paste any text — a single sentence, a paragraph, or a multi-thousand-line document. The diff algorithm works at the character and line level, making it a precise string comparer for any length of content.
Is this a good beyond compare alternative?
For text and code diffing in the browser, yes. It handles the most common use cases: comparing 2 strings, diffing documents, finding changed lines. No install needed — just open and compare.
Can I use this to compare two files like in notepad++?
Yes. Notepad++ has a compare plugin; this tool does the same thing in your browser. Paste the file contents, run the diff, and see exactly what changed — including options to sort lines and remove duplicates.
How do I compare two text files in Python?
If you need a quick visual diff without code, paste both files here. For scripted comparisons, Python's difflib module is the standard approach — our Python guide covers this in the Python landing page.
Compare XML, YAML, CSV & SQL
Online — Free, Instant, Private
Diff any structured data format in seconds. Compare XML files online, run a YAML diff, check CSV files for differences, or compare SQL code — all in one tool. No account required, nothing to install, and your data never leaves your browser.
Pick your format
Use the mode bar to switch between XML, JSON, YAML, CSV, SQL, HTML, CSS, or JavaScript compare modes.
Paste or upload
Paste your data directly or upload files. XML and JSON are normalised before diffing so whitespace and indentation don't create false positives.
See the diff
Every changed line is highlighted. Download the result as a unified patch file or copy specific changed sections.
Supported formats
- XML compare — compare xml online, xml comparer, xml comparator, xml comparison, xml diff checker, xmldiff, compare 2 xml files, compare xmls, online xml compare
- YAML diff — yaml compare online, compare yaml online, yaml difference, compare two YAML configs
- CSV compare — compare CSV files online, compare 2 csv files, csv compare online
- SQL compare — sql code compare online, compare sql online, sql comparison online, sqlcompare, compare sql databases, sql db comparison, sql compare strings, sql compare differences in two tables, match sql query
- JSON diff — compare two JSON objects, find added or removed keys
- Markdown diff — compare markdown documents for content changes, markdown validator
Why use this instead of a desktop tool?
Desktop tools like Beyond Compare are powerful but require installation and licences. This tool works instantly in any browser — Chrome, Firefox, Safari, Edge — with no setup. It handles the most common data format comparison tasks for free.
Useful for developers comparing configuration files, DBAs running sql query compare online, DevOps engineers doing yaml compare for deployment configs, and data analysts diffing CSV exports.
XML compare — what's supported
The XML compare mode supports: xml file compare, xml file comparison of any size, and detecting added, removed, or changed elements. Use it as an xml diff checker or full xml comparator — paste your XML or upload .xml files directly.
Handles xml difference detection cleanly even when whitespace varies. Also supports merge xml files workflows and compare to xml files tasks like API response validation.
Also supports merge xml files workflows — compare the source and target, then copy the merged result. Works for compare to xml files tasks like API response validation and config drift detection.
Data format comparison questions
How do I compare two XML files online?
Switch to XML mode, paste both XML files, and click Compare. The tool normalises whitespace first so you only see real structural differences. Works as an xml diff checker for both small snippets and large documents. Also works for compare 2 xml files tasks and as a full xml comparator.
What is xmldiff and how does this tool compare?
xmldiff is a command-line Python library for diffing XML files. This tool gives you the same xml difference detection in a browser — no install needed. Paste your xml files, get an instant diff. Good for compare two xml online tasks without any setup.
Can I do a YAML diff online?
Yes. Switch to the YAML mode, paste your two YAML configs, and run the diff. Useful for comparing Kubernetes manifests, Docker Compose files, or any yaml compare online task. Shows yaml difference line by line.
How do I compare CSV files online?
Use CSV mode or Excel mode. CSV mode does a line-by-line text diff. Excel mode parses all columns and rows so you can see which rows were added, removed, or changed — better for structured tabular data.
Can I compare SQL code online?
Yes. Switch to SQL mode. Paste two queries, stored procedures, or schema scripts. The diff highlights every changed line — useful for sql code compare online tasks like reviewing migration scripts, running a sql db comparison, or checking sql compare differences in two tables.
Does it work for merging XML files?
It shows you exactly what differs between two xml files, making merge xml files decisions straightforward. Copy the sections you want to keep from each side. It's not an automated merge tool, but it gives you the visibility to merge manually with confidence.
List Comparison Guides
Simple, Practical Answers
Short, helpful guides on comparing lists, finding duplicates, diffing files, and more. Written in plain English — no jargon.
How to Compare Two Lists Online (Free & Fast)
The simplest way to find what's different between two lists — no software, no formulas.
How to Find Duplicates in a List Online
Spot and remove repeated items from any list in seconds.
How to Compare Instagram Followers & Following
Find out who isn't following you back — without giving anyone your password.
Compare Two Lists in Excel — The Easy Way
Skip the VLOOKUP formulas. Here's a faster method that anyone can use.
Compare Two Lists in Python vs Online Tools
Code examples plus a no-code alternative for when you just need a quick answer.
How to Compare Two Lists Online
Free & Fast
If you've got two lists and want to know what's the same, what's different, and what's missing — this guide shows you the simplest way to do it online, in about 30 seconds.
Why compare lists online?
Maybe you have two customer lists and want to see who's in both. Or you exported data from two different systems and need to find the differences.
Or you just have two lists of names and want to know which ones overlap. Whatever the reason, doing a list comparison online is much faster than doing it manually or writing a formula.
How to do it — step by step
- Go to the tool — it's right at the top of this page. You'll see two text boxes: List A and List B.
- Paste your first list into List A. One item per line works best, but you can also use commas, semicolons, or tabs.
- Paste your second list into List B.
- Hit Compare (or press Ctrl+Enter). Results appear instantly.
You'll get four results: what's only in A, what's only in B, what's in both, and the full combined list. Each section has a copy button to grab the results right away.
Useful options to know about
Trim Spaces is on by default and removes accidental spaces before or after items. Remove Duplicates cleans out repeated items. Fuzzy Match catches near-matches like "John Smith" and "jon smith". 3 Lists mode lets you compare three lists at the same time.
✅ Everything is private. Your lists never leave your browser. Nothing is uploaded to any server.
How to Find Duplicates
in a List Online
In Seconds
Got a list with repeated items and want to clean it up fast? Here's the quickest way to find and remove duplicates from any list online — no Excel, no scripts, no hassle.
Why lists get duplicates
It happens all the time. You merge two exports and the same email appears twice. Someone adds a name to a spreadsheet that was already there.
You copy data from multiple places and end up with repeats. Finding them manually is tedious — this is where a free online duplicate finder saves you a lot of time.
How to find duplicates in your list
- Paste your list into the List A box at the top of this page.
- Watch for the yellow badge. As soon as duplicates are detected, a "⚠ dupes" badge appears. Click it to see which items are repeated.
- To remove them, turn on "Remove Duplicates" in the options bar, then hit Compare. The results show a clean, deduplicated list.
- Copy or download the clean list from the results panel.
Finding duplicates across two lists
If you want items that appear in both of two different lists, paste them into List A and List B, hit Compare, and look at the "In Both" results panel.
✅ Works with any list format. Items per line, comma-separated, semicolons, tabs — just change the separator dropdown to match your data.
How to Compare Instagram
Followers & Following
Find Who Doesn't Follow Back
Want to know who you follow that isn't following you back? Here's how to do it safely, without giving anyone your password.
First — download your Instagram data
- Open Instagram and go to Settings
- Tap Your Activity → Download Your Information
- Select Followers and Following and request the download
- Instagram will email you a download link — usually within a few hours
- Download and unzip the file. You'll find followers_1.json and following.json
Comparing the two lists
- Paste your followers list into List A
- Paste your following list into List B
- Hit Compare
- Only in A (Followers) — people who follow you but you don't follow back
- Only in B (Following) — people you follow who don't follow you back
- In Both — mutual follows
💡 Followers vs Following — your followers are people who follow you. Your following is the accounts you follow. The gap between these two numbers is exactly what comparing the lists shows you.
How to Compare Two Lists
in Excel
The Easy Way
Excel has a dozen ways to compare two columns — VLOOKUP, COUNTIF, conditional formatting. But if you just want a quick answer, there's a much simpler approach.
The Excel formula approach
The most common method uses COUNTIF to check whether each item in one column appears in the other:
It works, but it's fiddly — you need the right column references, handle headers, and filter the results.
The faster way — paste and compare
- Select the first column in Excel and copy it
- Paste it into the List A box on this page
- Copy the second column and paste it into List B
- Hit Compare — done in about 20 seconds, no formulas needed
Uploading Excel files directly
Even easier: switch to Excel Compare mode using the tab bar at the top, then drag and drop your .xlsx files into the upload boxes. The tool reads the data automatically.
💡 Tip: If your Excel columns have headers (like "Name" or "Email"), either include them in both lists or just skip copying the header row.
Compare Two Lists in Python
vs Using an Online Tool
Python is great for list comparison inside a script. But for a quick one-off answer, an online tool can save you 10 minutes. Here are both approaches.
When Python makes sense
Use Python when the comparison is part of a larger workflow — processing data, generating a report, or running the same comparison repeatedly. The code is repeatable and handles millions of items easily.
When an online tool is faster
Use an online tool for a one-off comparison. No environment setup, no script to write. Paste two lists and you're done in 30 seconds.
Python code examples
Find items in list A but not list B
only_in_b = list(set(list_b) - set(list_a))
in_both = list(set(list_a) & set(list_b))
Case-insensitive list comparison
b_norm = {x.strip().lower() for x in list_b}
only_in_a = a_norm - b_norm
🚀 No time to code? Paste both lists into the tool above. Turn off Case Sensitive and turn on Trim Spaces — that's roughly equivalent to the case-insensitive comparison above.
Built for Anyone Who
Needs to Spot Differences
List Compare Pro is a free, browser-based comparison tool for developers, analysts, writers, and anyone who needs to compare two pieces of content — without uploading sensitive data to a server.
What is List Compare Pro?
List Compare Pro lets you compare lists, code, text, JSON, XML, CSV, Excel, and PDF content instantly — with no account or software required. Everything runs locally in your browser, so your data never leaves your device.
Our Mission
We believe productivity tools should be fast, private, and free. List Compare Pro was built for the people who spend time every week manually scanning two files for differences — and want a better way.
Privacy First
All comparison processing runs entirely in your browser. No data is sent to any server during a comparison. The optional AI Summary feature sends only item counts and up to 3 example items — never your full data.
What We Offer
- 10 comparison modes: List, Text, JSON, XML, HTML, CSS, JavaScript, SQL, Excel/CSV, and PDF
- Fuzzy matching and regex filtering
- File upload — drag and drop .txt, .csv, .xlsx, .pdf and more
- AI-powered plain-English summaries
- Shareable links that encode your comparison in the URL
- CSV, JSON, and patch file download exports
- 3-list Venn comparison mode
- Dark mode, live comparison, and mobile support
Built With
List Compare Pro is a single-page HTML application. It uses SheetJS for Excel parsing, PDF.js for PDF text extraction, and the Anthropic API for AI summaries. No frameworks, no trackers, no cookies.
Also on List Compare Pro
Get in Touch
We Read Every Message
List Compare Pro is a small team and we'd love to hear from you — whether you've found a bug, have a feature idea, or just want to say hello.
Response Times
We aim to respond to all messages within 2 business days. For urgent issues, please include "URGENT" in your subject line.
Also on List Compare Pro
Your Data Stays
On Your Device
List Compare Pro is designed with privacy as a core principle. All comparison processing runs entirely within your browser — we do not operate servers that receive, store, or process the content you compare.
Last updated: March 2026
Data We Do Not Collect
We do not collect, transmit, or store the content you paste or upload into List Compare Pro. Your lists, code, documents, and files never leave your device during a comparison. We do not use cookies for tracking, do not run advertising networks, and do not sell any user data.
AI Summary Feature
The optional AI Summary feature sends a minimal prompt to the Anthropic API. This prompt contains only statistical information — the number of items in each set and up to 3 example items.
It does not contain your full data. If you do not click "AI Summary", nothing is sent. Anthropic's own privacy policy governs how they handle API requests.
Shareable Links
When you use the Share feature, your comparison content is Base64-encoded and embedded directly in the URL. This link is generated entirely in your browser and is never stored on our servers. Anyone who receives the link can view its contents, so only share links containing non-sensitive data.
File Uploads
Files you upload (including .xlsx, .pdf, .csv, and text files) are parsed locally in your browser using JavaScript libraries (SheetJS, PDF.js). File contents are not transmitted to any external server.
Analytics
List Compare Pro may use privacy-respecting, cookieless analytics to understand aggregate usage (page visits, which modes are most popular). This data is anonymised and never linked to individual users or their content.
Changes to This Policy
We may update this policy from time to time. The "last updated" date at the top of this page will reflect any changes. Continued use of List Compare Pro after changes constitutes acceptance of the updated policy.
Contact
Questions about this policy? Email us at gamevexo@gmail.com.