Gzip & Deflate Bundle Size Estimator
Measure exact payload compression sizes and bandwidth savings using CompressionStream API.
Execution runs 100% locally inside the browser sandbox using HTML5 Canvas, Web Cryptography Subtle API, and Web Workers. No data is ever transmitted across the network.
Zero network latency. Operates completely offline with zero dependencies on third-party backend servers or cloud services.
Built according to official RFC specifications, cryptographic test vectors, and enterprise-grade data transformation standards.
How to Use Gzip & Deflate Bundle Size Estimator
Paste your HTML, JS, CSS, or JSON payload into the workspace.
Inspect raw bytes vs. gzipped bytes and compression savings percentage.
Click to copy summary metrics to your clipboard.
Frequently Asked Questions
Is this an approximation or real Gzip?
It uses the real W3C CompressionStream('gzip') API in your browser to compute exact byte sizes.
Is my payload uploaded?
No, all compression calculations execute 100% locally in browser memory.
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