Original text
0 characters · 0 lines
Text Difference Checker
Compare an original and revised text and focus only on what changed.
How to use
- Enter the before and after versions of your text.
- Review additions, removals, and changes line by line.
- Optionally ignore spaces, line breaks, or letter case.
Revised text
0 characters · 0 lines
Comparison result
No changes
Added
Removed
Changed
Enter two texts to display the comparison result here.
Good for
Review changes between draft revisions, configuration text, email versions, or any two blocks of text.
About this tool
Compare revisions to email drafts, contracts, web copy, translations, code strings, and more. Comparison and draft storage take place only in your browser, and your text is never sent to a server.
Treat an edit and a moved line as different cases
Changing “Doors open at 9” to “Doors open at 10” shows 9 as removed and 10 as added. Reordering A, B, C to B, A, C is represented as removals and additions rather than a special move operation.
- The result describes string differences; it does not decide whether the revised statement is factually correct.
- When membership matters more than order, Compare Two Lists provides a clearer set-style comparison.
Try a use case and check the result
Distinguish edited lines from differences hidden by your comparison options.
Trying an example replaces the input and settings and runs the tool above. Restore previous input restores the preceding input and settings, not a saved copy of the calculated result; run again as needed. Existing storage rules apply.
After trying multiple examples, repeat Restore previous input to return to your original input. History is kept only in this page; restore any input you need before closing it.
Check a one-line edit
Input and settings
Before: red / blue (two lines) After: red / green (two lines) Ignore options: all off
Expected result
0 added · 0 removed · 1 changed blue → green
Ignore spacing and letter-case differences
Input and settings
Before: A B After: a b Ignore spaces and case: on Ignore line breaks and changes only: off
Expected result
No changes (under these comparison options)
How to read the result
Counts describe line differences. The first example replaces one line, so it reports one changed line. No changes in the second example does not mean the original strings are identical; disabling the ignore options reveals differences.
Scope and limits
This does not judge meaning or explain why an edit was made. Ignoring line breaks also hides paragraph boundaries. Comparisons that exceed the size budget stop while preserving input; character highlighting may be omitted for long lines. Normal 30-day draft-storage rules apply.
Verification: added, removed and changed counts from the existing buildLineDiff function, including option-dependent matching, are compared with the rendered summary and differences.
Continue with the next task
Compare with whitespace ignored
Example input
before: A B after: AB
Result
No changes
- Enter “A B” before and “AB” after.
- Toggle ignoring spaces and compare the result.
Ignoring spaces removes ordinary spaces, tabs, and full-width spaces from matching keys. Ignoring line breaks is a separate option.
An LCS comparison exceeding four million cells asks you to shorten the texts. Character highlighting has its own size limit.
Frequently asked questions
How are differences displayed?
Texts are compared line by line. Added, removed, and changed lines are color-coded, and changed lines also highlight character-level differences.
Can I ignore differences in spaces or line breaks?
Yes. You may separately ignore spaces, line breaks, and letter case in the comparison options.
Is my text sent to a server?
No. Comparison and draft storage take place only in your current browser.
Related tools
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Share only the tool name and public URL. Your input and results are not included.
Inputs and storage
Keep a separate copy before clearing or resetting. This browser autosaves entered text. Data is not restored when read 30 days or more after its last save. Clearing site data or storage restrictions may remove it sooner.
Favorites and language preferences are stored separately and may be lost when site data is cleared. Tool resets and site-data deletion do not delete files already downloaded to your device.