Text Diff Checker
Runs in browserCompare two texts and view line-by-line differences instantly.
Compare two text blocks and see line-by-line differences. Highlights added and removed lines. Useful for configs, code, or logs.
Text Diff Checker tool
View
Files never leave your browser.
Drag and drop a file here, or tap to select
Files never leave your browser.
Drag and drop a file here, or tap to select
Stats: +4 lines · −4 lines · 0 unchanged
Diff (line by line)
+ ToolDock is a free browser-based developer tools suite.+ All tools run entirely in your browser.+ No sign-up required, no data is ever sent to servers.+ Fast, private, and completely instant.- ToolDock is a free browser-based developer tools platform.- All tools run locally in your browser.- No sign-up required, no data sent to servers.- Fast, private, and instant.
🔒 Runs in your browser · No uploads · Your data never leaves your device
How to use
Enter text A and B
Paste the original text in the first area and the modified text in the second.
View diff
Added lines appear in green, removed in red, unchanged in default style.
Copy diff
Use Copy to copy the diff output.
Common use cases
- Comparing config file versions — Paste two versions of a config or YAML file to see exactly which lines changed between deployments.
- Reviewing prompt changes — Diff two LLM prompt versions to see what was added or removed before shipping.
Examples
Simple change
One line changed.
InputLine 1 Line 2OutputLine 1 - Line 2 + Line 2 updated
Frequently asked questions
- How is the diff computed?
- A line-by-line comparison: lines only in A are removed, only in B are added.
- Is my text sent anywhere?
- No. The diff is computed entirely in your browser.
Key concepts
- Diff
- A comparison of two text versions showing lines added (+), removed (−), and unchanged.
- Line-by-line diff
- A diff mode that compares texts one line at a time — standard for config files and code.
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