What is Two versions?
A before-and-after pair: config files, contract drafts, log excerpts or list exports. Reading them side by side invites mistakes — the eye cannot line up shifts reliably.
Text Diff Checker
Compare two texts and see changed lines
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How to compare two texts
Paste the original
Put the baseline text into the first input box.
Paste the changed text
Put the modified version into the second box (up to 100,000 characters).
Read the diff
Review or download the unified diff showing every added and removed line.
Frequently asked questions
How do I compare two texts?
Paste the original into the first box and the changed version into the second, then run the comparison to get a unified diff marking added and removed lines.
What are the size limits?
Each text can have at most 2000 lines, and the diff algorithm is capped at one million LCS cells. Exceeding either limit returns a clear error instead of freezing.
What is a unified diff?
The standard text format used by Git and code review: lines starting with + were added, − removed, and unchanged context lines are shown around them.
Are my texts uploaded?
No. The comparison runs entirely in your browser using a longest-common-subsequence algorithm — nothing leaves your device.
Line-by-line comparison
Here is what each format is for, and when converting two texts into one diff is the right move.
What is Unified diff?
A computed longest-common-subsequence diff that pinpoints exactly which lines were added and removed, in the standard format every developer tool understands.
When you need it
Use it to review what actually changed between two drafts, verify a find-and-replace pass, or spot differences in config and log files. For very large files, extract the relevant sections first — the 2000-line and 1M-cell limits are enforced honestly.