Diff Checker

Compare two texts line by line and see exactly what changed.

Original textNew text

Reading the diff

Lines prefixed with + were added in the new text and lines prefixed with - were removed. Unchanged lines have no marker. The comparison is line-based, which works well for JSON, logs, configs and code.

Use it to debug

Compare API responses between two environments.
Check what changed in a configuration file after toggling a flag.
Compare log output before and after a fix to confirm the expected lines changed.
Spot field-level changes in JSON fixtures when a schema shifts.

Testing tip

When a test fails with a large expected object, diffing the expectation against the actual response points straight at the changed field instead of scanning the whole payload by eye.