What is a text diff?
A text diff compares two versions of plain text and identifies what was added, removed, or changed. Developers use diffs during code review, writers use them to compare drafts, and teams use them to inspect configuration or data changes before publishing.
How line comparison works
The checker aligns lines that appear in both inputs, then marks unmatched lines as additions, deletions, or paired changes. Side-by-side view keeps each version in its own column, while inline view reads like a compact change log.
When to ignore whitespace or capitalization
Whitespace filtering is useful after automatic formatting changes, and capitalization filtering can help with prose or case-insensitive data. Leave both options off when spacing or letter case carries meaning, as it often does in source code and configuration files.
Common uses for a diff checker
Compare code snippets, edited copy, generated output, environment files, CSV rows, Markdown, JSON, XML, or any other text-based format. The comparison is line-focused, so it is best suited to structured text with meaningful line breaks.