Diff Checker
Paste your original and edited text into the two boxes below, and this diff checker highlights exactly what changed between them, added, removed or edited.
About
About Text Diff Checker
A diff checker compares two pieces of text and highlights exactly where they differ, word by word or line by line, instead of you having to scan both versions and spot the changes yourself. It's faster and far more reliable than reading through two documents side by side looking for what moved.
This comes up constantly when you're reviewing an edited draft, checking what a collaborator changed in a shared document, or comparing two versions of code, a contract, or any text that's gone through more than one round of edits. Reading both versions start to finish to catch every small change is slow and easy to get wrong, especially on longer documents.
A text diff checker works by aligning both pieces of text and marking anything added, removed or changed, usually with color coding, so additions and deletions are visually distinct at a glance rather than something you have to infer from reading closely.
Paste your original text into one box and the edited version into the other, and the comparison runs immediately, with differences highlighted directly in the output. There's no need to manually mark anything or scroll back and forth between two separate windows.
This is useful well beyond writing, developers use it to compare code snippets or config files, editors use it to review what changed in a manuscript, and anyone collaborating on a shared document can use it to quickly see what a teammate actually edited rather than re-reading the whole thing from scratch.
FAQ
Frequently asked questions
Does a diff checker compare word by word or character by character?
Most diff checkers, including this one, compare at the word level by default, which tends to be more readable for prose and general text. Some tools also offer a character-level or line-level comparison mode, useful for things like code where a single character change matters.
Can I use this to compare two versions of code?
Yes, comparing code works the same way as comparing regular text, pasting one version into each box shows exactly which lines were added, removed or changed. For very large files though, a dedicated code diff tool built specifically for that language might give more detailed context.
What do the different highlight colors mean?
Typically, added text is highlighted in one color (often green) and removed text in another (often red), so you can tell at a glance whether something was inserted or deleted, rather than just that something changed.
Is there a limit to how much text I can compare at once?
You can compare anything from a sentence to a full document, since the comparison runs in your browser rather than on a server. Very long documents may take a moment longer to render the comparison, but there's no hard size cap.
Can this tool detect if two documents are identical?
Yes, if there are no differences between the two texts, the tool will show no highlighted changes, which is itself a quick way to confirm two documents match exactly.
Does this tool store or save the text I compare?
No, everything is compared directly in your browser, so neither the original nor the edited text you paste in is uploaded or saved anywhere. That matters if you're comparing something sensitive, like a draft contract or private document.
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