All tools · 📐 Format / Inspect
🔍 Text Diff Checker
Paste old text on the left, new text on the right. See a line-by-line diff with additions in green, removals in red. Useful for comparing config files, contract revisions, or any two texts.
Examples
A: port=8080
B: port=9090- port=8080
+ port=9090Drop in both versions; deleted lines show in red, added lines in green.
Frequently asked questions
Is it word-level or line-level diff?
Line-level. For word-level diffs, you usually want a dedicated tool — line-level is faster and easier to scan for code/config.
Does whitespace count as a difference?
Yes by default. Trailing spaces and tab/space differences will show as changes.
How big can the inputs be?
Comfortably 10k+ lines on each side. Larger inputs may slow your browser; consider running git diff locally for very large files.
About this tool
Text Diff Checker runs entirely in your browser using standard Web APIs. No data is sent to any server. The source for this tool is in our public GitHub repository.
Related tools
- 🗂️ Sort & Dedupe Lines — Sort lines alphabetically, reverse, deduplicate, or filter empties.
- 🔍 Regex Tester — Test JavaScript regular expressions against input. See matches, groups, flags.
- 🗜️ HTML / CSS / JS Minifier — Strip whitespace, comments, and shrink HTML, CSS, or JavaScript.
Why this tool
vs typical free web-tool sites
| 1vw | Typical free site | |
|---|---|---|
| Price | Free | Free |
| Signup required | No | Often (for premium features) |
| Ads inside the tool | No | Yes (banner + video) |
| Data sent to server | No (browser-only) | Yes (inputs analyzed for ads) |
| Total tools | 96 | Often <20 or scattered across sites |
| Bookmarkable URL per tool | Yes | Mixed |
| Loads in under 1s | Yes (static) | Often slow (ad tracking) |
| Multilingual | EN / ES / PT / FR / DE | Usually EN only |
| Open source | Yes | No |