Brotli is an open-source lossless data compression algorithm developed by Google that achieves significantly higher compression ratios than Gzip for web assets.
Brotli (Content-Encoding: br) is a generic-purpose lossless data compression algorithm developed by Google in 2015. Combining a modern variant of the LZ77 algorithm, Huffman coding, and an embedded 120 KB static dictionary of common web words (HTML tags, JavaScript keywords), Brotli compresses web assets 15%–25% smaller than Gzip.
Inspect Content-Encoding response headers with the HTTP Headers Analyzer or analyze frontend script payloads with the Bundle Size Analyzer.
| Content Type | Gzip Savings (Average) | Brotli Savings (Average) | Additional Gain with Brotli |
|---|---|---|---|
| JavaScript (JS) | ~68% | ~76% | +8% to +14% smaller |
| CSS Stylesheets | ~72% | ~82% | +10% to +17% smaller |
| HTML Documents | ~70% | ~80% | +10% to +15% smaller |
| JSON API Payloads | ~65% | ~74% | +9% to +13% smaller |
Free, browser-based utilities to test, generate, and inspect Brotli (br) Compression Algorithm payloads directly.
Analyze HTTP response headers for security, caching, and compliance issues.
Analyze and visualize JavaScript bundle sizes with optimization suggestions.
Compress and optimize images to reduce file size without noticeable quality loss.
