Line Diff Counter Online
Compare two texts and count added, removed, and unchanged lines.
What Is a Line Diff Counter?
A Line Diff Counter is a free online tool that compares two blocks of text line by line and produces a summary of changes: how many lines were added, removed, and unchanged. It uses the Longest Common Subsequence (LCS) algorithm — the same approach used by git diff — to find the minimal edit distance between the two texts. The color-coded diff view highlights added lines in green and removed lines in red, making it easy to spot exactly what changed.
How to Use Line Diff Counter
- Paste the original text into the left panel.
- Paste the modified text into the right panel.
- Click Compare to run the diff.
- The stats bar shows added, removed, and unchanged line counts.
- The diff view below shows each line color-coded: green for added, red for removed.
Features
- LCS-based line diff algorithm (same as git diff)
- Summary stats: added, removed, unchanged, and total lines
- Color-coded diff view with + / - markers
- Works with any plain text: code, logs, config files, prose
- Runs entirely in your browser — zero data uploaded
FAQ
What is a Line Diff Counter?
A Line Diff Counter is a free online tool that compares two blocks of text line by line and counts how many lines were added, removed, or unchanged between them.
How does the diff algorithm work?
The tool uses the Longest Common Subsequence (LCS) algorithm to find the minimal set of changes between the two texts, the same approach used by git diff.
Is my text sent to a server?
No. All comparison happens entirely in your browser. Your text never leaves your device.
What is the difference between this and Text Diff?
Line Diff Counter focuses on counting and summarizing the number of added, removed, and unchanged lines. It also shows a color-coded diff view. Text Diff provides a more detailed side-by-side comparison.