When to use it
Use Text Compare whenever two versions of something need to match, or you need to know exactly why they don't. Writers use it to see what an editor changed in a draft. Freelancers use it to check a revised contract against the one they agreed to. Developers use it to spot the one changed value in a config file. In each case the question is the same: what changed, and where?
Reading the result
Removed text is marked in red and struck through. Added text is marked in green. In line mode, each line carries its number in the original and in the changed version, so you can jump straight to it in your editor. A line that was edited shows as one removed line followed by one added line. Switch to word mode to see which words inside it changed.
Frequently asked questions
Is my text uploaded anywhere?
No. The comparison runs entirely in your browser. Nothing you paste is sent to a server, which makes this tool safe for contracts, drafts and private code.
What is the difference between line and word mode?
Line mode compares whole lines and shows which were added or removed, with line numbers. It suits code, configuration files, lists and structured text. Word mode compares word by word and shows changes inline, which suits prose: edited paragraphs, contract revisions and rewritten drafts.
What do the ignore options do?
Ignore case treats "Draft" and "draft" as the same. Ignore whitespace, in line mode, treats lines as equal when they differ only in spaces, tabs or indentation. Word mode always compares words and ignores spacing between them.
How large can the texts be?
About 2,000 lines or words on each side, beyond the parts that are identical at the start and end. Past that, the tool asks you to compare smaller sections so your browser stays responsive.
How does the comparison work?
The tool finds the longest common subsequence: the largest set of lines or words that appear in both texts in the same order. Everything outside that set is shown as added or removed. This is the same principle behind version-control diff tools.