Text & Code Diff Checker
Compare two blocks of text line by line and see what changed. Paste an original and a modified version — two drafts of a paragraph, two versions of a config file, two API responses — and read the differences without setting up a repository or a diff tool.
How it works
- 1
Paste the original text into the left panel.
- 2
Paste the modified text into the right panel.
- 3
Read the line-by-line comparison to see what was added, removed or changed.
- 4
Fix the source in whichever system it came from, using the comparison as your checklist.
What people use it for
- Checking what an editor or collaborator changed in a document draft.
- Comparing a working configuration file against a broken one.
- Spotting the difference between two API responses or log excerpts.
- Reviewing a snippet someone pasted against the version you have.
Supported formats & options
| Input | Any two blocks of plain text, pasted into the two panels |
|---|---|
| Comparison | Line-by-line, in document order |
Key advantages & benefits
No repository needed
Compare text that was never in version control — a pasted email, a config value, a CMS field.
Line-level clarity
Differences are shown per line, which is the granularity people actually reason about when reviewing changes.
Works on any text
Prose, code, JSON, logs, configuration — anything you can paste as text.
Content stays local
Both versions stay in the browser, so comparing a contract draft or a production config is safe.
Limits & things to know
- The comparison is line-based. A change to a single word marks the whole line as changed rather than highlighting the individual word.
- Very long documents get harder to scan in a two-panel view; compare a section at a time for large files.
- Line-based comparison is sensitive to formatting — reflowing a paragraph or changing line endings marks lines as different even when the wording is identical.
Troubleshooting
Everything is marked as changed
Usually a line-ending or wrapping difference — one version uses hard line breaks, the other does not. Normalise the wrapping in both panels before comparing.
A moved block shows as one deletion and one addition
That is how line-based comparison represents a move. Read the pair together rather than treating it as two separate edits.
Privacy & data handling
Both texts stay in your browser and are compared locally. Nothing is uploaded, which makes it safe for contracts, credentials-adjacent configs and unpublished drafts.
Text Diff Checker — Compare Two Texts Online Free
Compare two blocks of text and see exactly what changed, line by line. This free text diff checker highlights additions, deletions and edits between two versions of a document, contract, config file or code snippet without installing a diff tool.
- Line-by-line comparison — added lines, removed lines and modified lines are colour-coded so a single changed character in a long file is impossible to miss.
- Compare document revisions — check what a client, editor or colleague actually changed between two drafts before you accept the new version.
- Diff code and config files — compare two versions of an environment file, a YAML manifest or a function when you do not have version control to hand.
- No file size or usage limits — paste as much text as you like, as often as you like — there is no free tier to run out of.
- Confidential by default — contracts, legal clauses and internal documents are compared entirely in your browser and never uploaded for processing.
Free and account-free. Use the JSON Formatter first when you are diffing two API responses — formatting both sides makes the real difference obvious.
Frequently asked questions
Is there a limit on text length?
No limit! You can compare thousands of lines of code or text effortlessly.
Why is every line marked as changed?
Almost always a wrapping or line-ending difference — one version has hard line breaks where the other has flowing text. Normalise the wrapping in both panels and compare again.
Can it highlight the specific word that changed?
No, the comparison is line-based, so a one-word edit marks the whole line. That granularity matches how most people review changes, but it is coarser than a word-level diff.
Is it safe to paste confidential text?
Both versions stay in your browser and are compared locally, so nothing is uploaded. That is what makes it usable for contracts, configuration files and unpublished drafts.
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