Compare two text blocks with line-by-line diff. Additions highlighted green, removals red. Unchanged sections collapse automatically.
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+/-/space prefixes).Line diff
Each line is compared as a unit. A line is either added, removed, or unchanged. Best for code, configuration files, or any content where lines are meaningful units. This is the mode used by git diff and most version control systems.
Word diff
Individual words are compared. Useful for prose, documentation, or any content where you want to see exactly which words changed within a paragraph rather than which entire lines changed.
Paste the original text into the left panel and the modified text into the right panel. The diff updates automatically as you type. Toggle between Line diff and Word diff modes depending on how granular you need the comparison. Use Copy Diff to copy the result in unified format for use elsewhere.
Text diff compares any two texts line by line. It treats JSON as plain text, so reformatting or reordering keys appears as changes even when the data is semantically identical. JSON Diff parses the structure and compares semantically, so key order and whitespace changes produce no output. Use text diff for comparing exact file contents and JSON Diff for comparing data.
Use the Copy Diff button to copy the diff in unified format. You can paste this into a GitHub comment, a Slack message, a document, or a .patch file. The unified format (lines prefixed with + and -) is widely understood and displays clearly in monospace fonts.
Yes, by default. A line with a trailing space and the same line without it are treated as different. This matches the behavior of git diff and most code comparison tools. If you want whitespace-insensitive comparison, trim your input before pasting.
Yes. Paste the entire file contents into each panel. The diff engine treats any text as plain text with no language awareness. The output is equivalent to running git diff --unified on two files.
The diff uses the Myers diff algorithm, the same one used by git diff and GNU diff. It finds the shortest edit script (minimum number of additions and removals) needed to transform the left text into the right text.
Copying produces a simplified unified diff: lines prefixed with + (added), - (removed), or a space (unchanged). All lines are included without context collapse. This format is compatible with patch files and is human-readable without any additional tooling.
No. All diffing runs in your browser using the open-source jsdiff library. Paste production config files, SQL schemas, and private API responses without concern.
JSON Diff
Compare two JSON objects side-by-side and highlight differences.
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