CSS & JS Minifier

Frequently asked questions

Is this production-grade minification?

It covers the most impactful steps — comment removal and whitespace collapse — which typically yield 30–60% reduction on real stylesheets. It does not perform advanced optimizations like dead-code elimination, property shorthand merging, or variable inlining. For production, use a dedicated tool like cssnano, esbuild, or Terser in your build pipeline.

Will it break my CSS selectors or string literals?

CSS minification uses a simple regex pass that collapses whitespace around punctuation — it doesn't parse the full CSS grammar. For standard stylesheets this is safe. Very unusual selectors or data URIs with embedded spaces could theoretically be affected, so always test the minified output.

Does JS minification rename variables?

No. This tool removes comments and collapses whitespace — it doesn't mangle variable or function names. For full mangling, use esbuild, Terser, or Google Closure Compiler in a build step.

Is my code uploaded anywhere?

No. Minification runs entirely in your browser using JavaScript regex replacements. Nothing is sent to a server — safe for proprietary stylesheets and internal scripts.

Why is the reduction sometimes small for JavaScript?

Whitespace-only minification has diminishing returns on already-compact code or on code with few comments. The biggest wins come from removing block comments and collapsing indentation; files with minimal whitespace to begin with may only shrink by 10–20%.

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