Private
Never leaves your browser
Diffs are computed on your device in a background worker. No uploads, no accounts, no tracking of your text.
Online Diff Checker · Private · Free
Diff Checker — find every difference, instantly.
Paste or drop two versions of any text, code, HTML or file. See additions, removals and edits highlighted line by line — right in your browser.
View
Regular expression. Matching text is ignored when comparing lines.
Results appear here.
Paste two texts to see what changed
Everything runs in your browser — your text is never uploaded. Drop files, paste code, JSON or prose.
Texts changed — press Find Difference to update.
Shortcuts: ⌘↵ compare · ] next change ·[ previous change · ·
Features
A free diff checker with everything you need. Nothing behind a paywall.
Clear
Removals & additions at a glance
One click on Find Difference (or ⌘/Ctrl + Enter) gives exact removal and addition counts for each side, with line totals.
Syntax
Code highlighting, free
Auto-detects 20+ languages — TypeScript, Python, Go, JSON, SQL and more — and colors the diff like your editor.
Moves
Moved code, not deleted code
Blocks that moved are marked “moved” with a jump link to their new place, instead of a scary removal plus addition.
Merge
Accept changes per block
Copy any change from one side to the other with one click — with undo — to build the final version right in the tool.
Precision
Smart, word or character
Edited lines pair with their closest match. Ignore whitespace, case or any regex such as timestamps and IDs.
History
Your checks, saved locally
Every comparison is saved to this browser automatically. Search, reopen or delete — or turn history off entirely.
Share
Links without sign-up
Share a diff with a link. The text is compressed into the link itself, so nothing is stored on a server.
Export
Patch, .diff & PDF
Copy a unified patch for Git, download a .diff file, or save a clean PDF of the comparison.
Adaptive
Fits your device
Auto-detects your screen and theme: split view on desktop, unified on phones, and dark mode when your system is dark.
AI
Private AI summaries
Get a plain-English summary of what changed, generated on your device by Chrome’s built-in AI. Nothing is uploaded.
Fast
Built for large files
An efficient line diff in a Web Worker keeps typing smooth even with tens of thousands of lines.
About the Tool
The free online diff checker for text, code and files
Easy Diff Checker is a free online diff checker that compares two pieces of text and shows exactly what changed between them. Paste the original version on the left and the changed version on the right, press Find Difference, and every added, removed and edited line is highlighted side by side. Whether you call it a diff checker online, a text compare tool or a “find the difference” utility, the goal is the same: see changes in seconds instead of reading two documents line by line.
What is a diff checker?
A diff checker runs a difference algorithm — the same idea behind Git’s diff command — over two inputs and reports the smallest set of insertions and deletions that turns one into the other. A good diff checker goes further: it pairs edited lines with their closest match, highlights the exact words or characters that changed, and recognizes when a block of code has simply moved. Easy Diff Checker does all of this in your browser, so the comparison is fast and your text is never uploaded to a server.
A text diff checker and code diff checker in one
As a text diff checker, it is ideal for contracts, essays, translations, emails and configuration files. Switch between smart, word and character precision, and ignore whitespace, letter case or any regular expression such as timestamps and IDs. As a code diff checker, it detects more than 20 languages — TypeScript, JavaScript, Python, Go, Java, C#, PHP, SQL, YAML and more — and applies syntax highlighting so the diff reads like your editor. It also works as an HTML diff checker: paste two versions of a page, template or email and spot changed tags and attributes instantly. Export a unified patch for Git, download a .diff file or save the comparison as a PDF.
A file diff checker without uploads
Don’t want to copy and paste? Use Open File or drag and drop to turn the page into a file diff checker. Any plain-text file — logs, source code, .env files, Markdown, XML or exported data — is read locally by your browser. Because nothing leaves your device, you can safely compare credentials, customer data or unreleased source code. For Word, PDF and PowerPoint files, use the docs and file diff checker.
Specialized diff checkers for every format
Plain text is only the beginning. Easy Diff Checker includes a family of free diff checker tools, each tuned for its format:
- JSON diff checker — compares JSON by meaning, ignoring key order, matching arrays by id and exporting JSON Patch.
- Excel diff checker and CSV diff checker — compares XLSX, XLS, ODS and CSV files cell by cell, with rows matched by ID.
- Image diff checker — image compare online with slider, fade, blink and pixel-difference modes, plus highlighted changed regions.
- List diff checker — shows what is only in list A, only in list B and in both, with duplicates flagged.
- Folder diff checker — compares two folders or .zip archives and opens a line-by-line diff for any modified file.
- Docs diff checker — Word, PDF and PowerPoint files, even a PDF against a Word document.
How to use the diff checker
- Paste or drop the original text into the left pane.
- Paste or drop the changed text into the right pane.
- Press Find Difference or ⌘/Ctrl + Enter, then review the highlighted changes, jump between them, merge blocks from one side to the other, or share the result with a link.
Why choose Easy Diff Checker?
Many online diff checker sites upload your text, limit file size or hide features behind a paywall. Easy Diff Checker is different. It is completely free, needs no account, and runs in a Web Worker so even files with tens of thousands of lines stay smooth. Your history is saved only in this browser, share links keep the content inside the URL fragment, and the app works offline once installed. Bookmark it as your everyday diff checker for text, code and files.
Privacy by Design
Your text stays on your device.
Contracts, source code, credentials in config files — compare them without worrying. There's no server-side processing, no account and no copy of your content anywhere but your browser.
// where your text goes
compare → this browser (Web Worker)
history → this browser (localStorage)
share → inside the link (#fragment)
server → nothingFAQ
Questions & answers
What is a diff checker?
A diff checker compares two versions of text, code or a file and highlights exactly what was added, removed or changed between them. Easy Diff Checker is a free online diff checker that does this instantly in your browser.
Is my text uploaded anywhere?
No. Easy Diff Checker compares your text entirely inside your browser. Nothing you paste is sent to our servers.
Where is my diff history stored?
In your browser’s local storage on this device only. You can search, delete individual checks, clear everything, or turn history off from the History panel.
How do share links work without an account?
Both texts are compressed into the part of the link after the # sign. Browsers never send that part to a web server, so the content stays between you and whoever you send the link to.
Can I compare code, HTML, JSON, CSV or logs?
Yes. Any plain text works, and code and HTML get syntax highlighting. Use Format JSON to normalize JSON first, and an ignore pattern to skip timestamps or IDs in logs. For semantic JSON, Excel and CSV comparison, use the dedicated JSON diff checker and Excel & CSV diff checker.
Can I compare two files instead of pasting text?
Yes. Click Open File or drag and drop a file onto either side to use it as a file diff checker. Files are read locally by your browser and never uploaded.
How do I switch between light and dark mode?
By default the site follows your device’s theme automatically. Use the System / Light / Dark switch in the header to override it; your choice is remembered.
Does the AI summary send my text anywhere?
No. “Summarize with AI” uses the AI model built into Chrome, which runs on your own computer. If your browser doesn’t have it, you can copy a ready-made prompt and paste it into an assistant you trust — nothing is sent automatically.
Is it free?
Yes. Every feature — split and unified views, syntax highlighting, moved-code detection, word and character precision, merge, history, sharing and export — is free with no sign-up.