CSS Compare

How CSS Compare works

A plain text diff on a stylesheet flags changed lines, so reordering declarations or reformatting whitespace shows up as noise even when nothing actually changed visually. CSS Compare instead parses both snippets into rules (selectors and, separately, each selector nested inside an @media or @supports block) and compares them property by property. For every selector you get one of four verdicts: the rule was added, removed, changed (with each property's old and new value shown), or left unchanged. Comments are ignored, and declaration order within a rule does not affect the result, but property values are compared as exact strings — so #fff and #ffffff are reported as a change even though a browser renders them identically. Everything runs locally in your browser — nothing you paste is uploaded anywhere.

Related tools: the CSS formatter, the text diff tool, and the CSS specificity calculator.