Compress or decompress a real file — or pasted text/Base64/Hex — with GZip, Deflate or Brotli, and download the exact result. 100% locally in your browser.
or drop it here — compressed in your browser, never uploaded.
{{ compFile.name }}{{ humanSize(compFile.size) }}
{{ compError }}
{{ compOutput }}or drop it here — a .gz/.br file, decompressed in your browser
{{ decompFile.name }}{{ humanSize(decompFile.size) }}
{{ decompError }}
{{ decompOutput }}Binary content ({{ decompBytesOut.length }} bytes) — not valid UTF-8 text, so there's no preview. Download the file to view it.
GZip, Deflate and Deflate-raw use the native browser CompressionStream / DecompressionStream Web APIs. Browsers have no native Brotli in JavaScript, so Brotli runs through a local WebAssembly build — still fully client-side, no CDN.
Both modes accept a real file (drag it in or use the file picker) as well as pasted text — output always includes a "Download" button that saves the exact compressed or decompressed bytes, not just a Base64/Hex string. Decompressing a file whose content isn't text (an image, an archive, ...) works too: there's no text preview since it isn't valid UTF-8, but the download is byte-for-byte correct.
No network requests: files and text are processed entirely in local memory and never leave your browser.
