📦 GZIP Compressor & Decompressor
Compress or decompress data using GZIP. Runs entirely in your browser.
Last updated: May 18, 2026 · By Λ
Free GZIP Compressor & Decompressor
Compress text or files using the GZIP algorithm directly in your browser. View compression statistics including ratio, original size, and space savings. Decompress GZIP data back to its original form. Uses the browser's built-in CompressionStream API for fast, reliable compression. The whole gzip pipeline runs inside this tab, so the bytes you feed in stay on your computer from start to finish.
What is GZIP Compression?
GZIP is a widely used data compression algorithm based on the DEFLATE method, which combines LZ77 encoding and Huffman coding. It was originally created for the GNU project and has since become one of the most common compression formats on the internet. Web servers routinely use GZIP to compress HTML, CSS, JavaScript, and JSON files before sending them to browsers, significantly reducing transfer times and bandwidth usage.
This free online tool lets you compress and decompress data using GZIP directly in your browser. Developers can quickly test compression ratios on text content, compress files before transferring them, or decompress GZIP data they have received. Because the tool uses the browser's built-in CompressionStream API, it is fast, reliable, and completely private. Whatever you compress here is handled on your own hardware rather than on a remote machine.
How to Use This Tool
- Choose between "Compress" and "Decompress" mode using the tabs at the top of the tool.
- Select your input method: type or paste text directly, or switch to file mode and upload any file by clicking or dragging it into the drop zone.
- Click the action button to compress or decompress your data. The result appears in the output area, and detailed statistics show the original size, result size, compression ratio, and space savings.
- Copy the base64-encoded output to your clipboard, or download the raw compressed or decompressed file directly.
Key Features
- Compress and Decompress - Switch between compression and decompression modes with a single click. Both directions are fully supported.
- Text and File Input - Work with plain text by typing or pasting, or upload entire files of any type for binary compression.
- Detailed Statistics - View original size, compressed size, compression ratio, and percentage of space saved after every operation.
- Base64 Output - Compressed data is displayed as a base64 string for easy copying and sharing in text-based contexts like APIs or configuration files.
- Native Browser API - Uses the CompressionStream and DecompressionStream APIs built into modern browsers for reliable, high-performance compression.
Frequently Asked Questions
What types of data compress well with GZIP?
Text-based data compresses extremely well with GZIP. HTML, CSS, JavaScript, JSON, XML, and plain text files can often be reduced by 60% to 90%. Binary files like images, videos, and already-compressed archives typically see little to no size reduction because they already use their own compression schemes.
Which browsers support the CompressionStream API?
The CompressionStream API is supported in Chrome 80 and later, Edge 80 and later, Firefox 113 and later, and Safari 16.4 and later. If your browser does not support this API, the tool will display a compatibility message at the top of the page.
Is GZIP the same as ZIP?
GZIP and ZIP both use the DEFLATE compression algorithm, but they serve different purposes. GZIP compresses a single stream of data, while ZIP is an archive format that can bundle multiple files and directories into one package. GZIP is primarily used for compressing individual files and for HTTP content encoding on the web.
Is my data safe when using this tool?
Yes. All compression and decompression happens entirely in your browser. No data is sent to any external server. You can verify this by disconnecting from the internet and confirming the tool still works. Your files and text remain completely private.