Does this tool diff word by word or line by line?

Line by line. That is the right granularity for prose edits, config files, code review, and log comparisons. Word-level diffing is useful when you already know the two texts are close, but it gets noisy on larger edits.

What algorithm does it use?

A standard longest-common-subsequence (LCS) dynamic-programming diff. It finds the longest alignment between the two inputs and classifies the rest as inserts or deletes. Memory use is O(n·m), which is fine for inputs up to a few thousand lines each.

Is my text uploaded anywhere?

No. All comparison happens in your browser — safe for legal redlines, private emails, and internal code. Nothing is sent to a server and nothing is stored between visits.

Can I use this to diff code or JSON?

Yes, though a language-aware tool may give better hunks for code. For JSON in particular, run both sides through the JSON Formatter first — that normalizes key order and whitespace, so the diff shows the real semantic changes rather than spurious formatting differences.

Text Diff Viewer

Paste two versions of any text and see a line-level diff. Added lines are green, removed lines are red.

Original text

Changed text

Options

Ignore caseIgnore whitespace

How to diff two pieces of text with MakeMyTxt

Paste two versions of any text and see a line-by-line comparison with colored additions and deletions.

Open the Text Diff Viewer
Visit makemytxt.com/text-diff-viewer. The page loads two empty textareas side by side — the "original" on the left, the "changed" version on the right.
Paste both versions
Drop the original text on the left and the revised text on the right. The diff recomputes on every keystroke — there is no Submit button to click.
Tune the comparison
Use "Ignore case" when you only care about substantive content and not capitalization. Use "Ignore whitespace" when formatting noise (extra spaces, trailing tabs) is hiding the real changes.
Read the output
Green rows starting with + are additions from the right side. Red rows starting with − are deletions from the left side. Unchanged rows are dimmed. Line numbers on the left and right give you a reference for each side.

Frequently asked questions

Does this tool diff word by word or line by line?: Line by line. That is the right granularity for prose edits, config files, code review, and log comparisons. Word-level diffing is useful when you already know the two texts are close, but it gets noisy on larger edits.
What algorithm does it use?: A standard longest-common-subsequence (LCS) dynamic-programming diff. It finds the longest alignment between the two inputs and classifies the rest as inserts or deletes. Memory use is O(n·m), which is fine for inputs up to a few thousand lines each.
Is my text uploaded anywhere?: No. All comparison happens in your browser — safe for legal redlines, private emails, and internal code. Nothing is sent to a server and nothing is stored between visits.
Can I use this to diff code or JSON?: Yes, though a language-aware tool may give better hunks for code. For JSON in particular, run both sides through the JSON Formatter first — that normalizes key order and whitespace, so the diff shows the real semantic changes rather than spurious formatting differences.

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