Diff Checker | How to use and interpret results
Compare two texts as ordered lines and mark additions, removals and unchanged sections. A longest-common-subsequence comparison suits short configuration files and draft paragraphs.
- Runs in your browser
- Nothing is uploaded
- No signup; device limits apply
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How to use this tool
Paste the older and newer versions into their respective boxes. A changed line break can appear as a change even when the words match, so preserve the original line structure.
Results and examples
Two-line A, B compared with A, C keeps A and marks B removed and C added. The change count includes that removal and addition separately.
Worked example
Two-line A, B compared with A, C keeps A and marks B removed and C added. The change count includes that removal and addition separately.
Limitations
- This does not judge meaning or writing quality.
- Large pairs of line sets can require substantial time and memory.
Fields
| Field | Guidance and constraints |
|---|---|
| Original (A) | Check the unit and format displayed beside this field. |
| Compare (B) | Check the unit and format displayed beside this field. |
| Line-by-line diff | Check the unit and format displayed beside this field. |
Data handling
Processing stays in the current browser tab; the site does not upload tool input for the calculation itself.
Sources
Frequently asked questions
Why does replacing one line count twice?
Two-line A, B compared with A, C keeps A and marks B removed and C added. The change count includes that removal and addition separately.
Is a very large comparison instantaneous?
This does not judge meaning or writing quality. Large pairs of line sets can require substantial time and memory.
