Gzip / Zlib / Deflate Tester

Gzip / Zlib / Deflate Tester

Compress and decompress data using gzip, zlib, and raw deflate formats directly in your browser. Test compression output, verify data integrity, and measure size savings — all client-side with no data leaving your machine.

How to Use

1. Choose your mode: Compress or Decompress.

2. For compression: paste text or upload a file, select the format (gzip, zlib, or deflate), and click compress.

3. For decompression: paste base64 or hex encoded compressed data, and the tool auto-detects the format.

4. View the result along with size metrics showing original size, compressed size, and compression ratio.

5. Copy the output or download it as a file.

Features

• Three Formats – Compress and decompress with gzip, zlib, and raw deflate
• Auto-Detection – Automatically identifies compression format from magic bytes (1f 8b for gzip, 78 xx for zlib)
• Size Metrics – See original size, compressed size, and compression ratio percentage
• Multiple Output Formats – View compressed data as base64 or hex, or download as binary file
• File Support – Upload files for compression and download compressed/decompressed results
• Data Validation – Verify integrity of compressed data with clear error messages
• Client-Side Only – Uses browser-native CompressionStream API; no data sent to any server