DevToolbox

Diff Checker

Compare two text blocks line by line to spot additions, removals, and unchanged lines. Useful for config reviews, prompt revisions, copy edits, and code-adjacent text comparisons.

Added
2
Removed
1
Unchanged
5

Unified diff

name: DevToolbox
-theme: light
+theme: dark
features:
- json formatter
- regex tester
- timestamp converter
+ - jwt decoder

Common use cases

Practical ways developers use the diff checker in real workflows.

Review config changes

Compare two versions of a config file to spot exactly which settings were added, changed, or removed.

Check copy edits

Paste original and edited text side by side to see what a reviewer or editor changed.

Verify deployments

Diff the before and after of an API response or output to confirm a code change had the intended effect.

Frequently asked questions

Short answers to the questions people usually have before using the tool.

What diff algorithm does this tool use?+

It performs a simple line-by-line comparison, highlighting added, removed, and unchanged lines between the two inputs.

Can I compare code files?+

Yes. Paste any two text blocks — code, config files, or prose — and the tool shows the differences line by line.

Does it handle large files?+

The tool works well for typical text comparisons. For very large files (thousands of lines) a desktop diff tool may be more practical.

Related tools

Keep moving through related utility tasks without leaving the toolbox.