Text Compare: How to Diff Two Texts Online

Quick Answer

This diff checker lets you compare text and see exactly what is different between two versions. Paste the original in the first box and the new version in the second to compare two texts side-by-side. This text diff marks the added and removed lines: additions appear in green with a + marker, removals in red with a - marker, and unchanged lines are greyed out. A similarity percentage shows how much of the text is shared.

Why Text Comparison Matters

Spotting the text difference between two drafts by eye is slow and error-prone: a moved clause or a deleted sentence is easy to miss. Automatic change detection does the reading for you, putting the two versions side-by-side and marking every line that differs. That matters when the stakes are real, such as a contract edit, a policy update, or a paragraph that changed between reviews, where knowing exactly what moved is the whole point.

How to Use Text Compare

1. Paste the original version of your text into the Original box.
2. Paste the new version into the New Text box.
3. The diff appears instantly below both inputs.
4. Green lines with + were added in the new version.
5. Red lines with - were removed from the original.
6. Greyed lines with a space were unchanged.

Reading the Diff Output

The diff format used here is the same convention as diff and git diff on the command line:

• + (green background): line present in the new text but not the original
• - (red background): line present in the original but not the new text
• space (muted): line present in both texts, unchanged

How are differences detected? The tool aligns the two inputs line by line and marks any line that appears on only one side. One consequence: whitespace and case differences can show as changes, because "Hello" and "hello ", or a line with a trailing tab, are not identical strings. Remember a diff shows what changed, it does not merge: it reports the added and removed lines and leaves the editing to you. The stats bar above shows the totals plus a similarity percentage.

When to Use Text Compare

• Proofreading two drafts of a document to see what changed
• Comparing contract versions to find inserted or removed clauses
• Reviewing code changes before committing (for quick checks outside a code editor)
• Checking that a translation or paraphrase preserved the original structure
• Auditing content updates on a webpage by comparing old and new versions

Common Mistakes

Related tools: explore all text utilities in the Text Utilities collection, including Find and Replace, Word Counter, and Remove Duplicate Lines.