Diff Checker — Compare Two Texts and See the Differences Clearly
Comparing two versions of a text, config file, or API response is a common task for developers. A diff checker that runs in the browser lets you paste the original and modified text and see exactly what was added, removed, or unchanged—without sending your data to any server. This is useful for reviewing config changes, comparing API responses, checking log differences, or verifying that a transformation produced the expected output. The tool shows a line-by-line diff with color-coded highlights: green for added lines, red for removed lines, and no highlight for unchanged lines. You also get a summary of how many lines were added and removed. All processing happens locally, so your data stays private. Whether you're debugging, code-reviewing, or just comparing two pieces of text, a clear diff view saves time and reduces errors.
What Does This Tool Do?
This tool compares two text inputs (original and modified) and shows a line-by-line diff. You paste the original text in the left area and the modified text in the right area, then click Compare. The tool computes the differences and displays them in a table with line numbers, change indicators (+/-/space), and color-coded content: green background for added lines, red background for removed lines, and no highlight for unchanged lines. A summary at the top shows the total number of added and removed lines. All processing runs in your browser; no data is sent to any server. The diff algorithm works on a line-by-line basis and handles additions, deletions, and modifications. You can clear both inputs and the result when you're done.
How to Use It (Step-by-step)
Paste the original text in the Original text area.
Paste the modified text in the Modified text area.
Click Compare. The diff result appears below with color-coded highlights.
Review the summary showing how many lines were added and removed.
Scroll through the diff to see each change.
Use Clear to reset all inputs and results.
Key Features & Use Cases
- Client-side only: no data is sent to a server.
- Side-by-side input areas for original and modified text.
- Line-by-line diff with color-coded highlights (green for added, red for removed).
- Summary showing total added and removed lines.
- Line numbers for easy reference.
- Compare two versions of a config file to see what changed.
- Review API response differences between environments.
- Check log file changes between runs or deployments.
- Verify that a text transformation produced the expected output.
- Code review: compare before and after versions of a snippet.