Diff Checker
Compare two texts and highlight the differences line by line.
Original
Modified
Examples
Input
Original: 'Hello world' Modified: 'Hello Toolzmint'
Output
− Hello world + Hello Toolzmint
Input
Two versions of a config file or code snippet
Output
Added lines highlighted in green, removed lines in red, unchanged lines shown normally
About this tool
Use this diff checker to compare two pieces of text and see exactly what changed between them. It highlights added lines in green and removed lines in red, making it easy to spot edits in code, documents, configs, or any text.
How to use
- Paste the original text in the left panel.
- Paste the modified text in the right panel.
- Review the highlighted diff below showing what was added, removed, or unchanged.
What a diff checker is used for
A diff checker compares two texts and shows exactly what changed between them. It is useful for reviewing edits in documents, comparing config files, spotting changes in code, or verifying that two versions of content match expectations.
Instead of reading through both texts manually, a diff tool highlights the differences so you can focus only on what changed.
Line-by-line comparison
This tool compares text line by line. Added lines in the modified version are shown in green and removed lines from the original are shown in red. Unchanged lines appear without highlighting so the overall structure stays readable.
FAQ
Does this work for code?
Yes. You can paste any text including code, configuration files, JSON, markdown, or plain prose.
How are differences calculated?
The tool uses a line-level diff algorithm to identify which lines were added, removed, or left unchanged between the two inputs.
Is there a size limit?
There is no hard limit, but very large texts may take a moment to process since everything runs in your browser.
Related Tools
JSON Formatter
Format and validate JSON instantly.
Open tool
Duplicate Line Remover
Remove duplicate lines from text.
Open tool
Line Sorter
Sort text lines alphabetically instantly.
Open tool
CSV to JSON
Convert CSV data to JSON instantly with support for headers, custom delimiters, and pretty print.
Open tool
Word Counter
Count words, characters, and sentences instantly.
Open tool
Character Counter
Count characters instantly with or without spaces.
Open tool