Text Diff Viewer

The Text Diff Viewer compares two blocks of text and shows you exactly what changed, line by line. It highlights additions and removals so you can review an edit, audit a config change, or verify that two versions of a file really are different only where you expected. You can ignore whitespace or blank lines to focus on the meaningful edits, which is especially helpful when a tool reformats code and floods the diff with noise. Paste the old version on one side and the new one on the other and the viewer takes care of the rest. Comparing two versions of a text by eye fails as soon as the file is longer than a screen, because the eye cannot hold one version in memory while reading the other. A line based diff solves that by computing what changed and marking each line as added, removed, or unchanged, which reduces a review to reading only the lines that actually differ. The most common real task is reviewing an edit you or someone else made: the diff shows whether the change is as small as intended, and a change that should have touched one line but touched a dozen is usually a sign that a formatter ran or a paste landed in the wrong place. Whitespace handling is the setting that matters most in practice, because a tool that reindents code turns a meaningful one line change into a screen full of noise, and ignoring whitespace or blank lines brings the signal back. It is equally useful for auditing a configuration change, confirming that two supposedly identical files truly match, and checking that a transformation did only what it claimed.

📘 Related guide: Test a regex against live sample text before deploying →