Compress and decompress text in your browser · Supports Gzip and Deflate · Real-time compression ratio · Pure frontend
📖 Frequently Asked Questions (FAQ)
❓ What is gzip compression used for? When should I compress text?
Gzip is a widely-used data compression format commonly used for: 1) Web performance — servers gzip HTML/CSS/JS before sending, reducing transfer size by 70-90%; 2) API data transfer — compressing JSON payloads reduces bandwidth; 3) Log and file storage — compressing large text files saves disk space; 4) Web scraping — compressed data transfer; 5) Message queues — compressing messages improves throughput. Use this tool to test and verify compression before implementing it.
❓ What is the difference between Gzip and Deflate? Which should I choose?
Gzip and Deflate both use the DEFLATE compression algorithm but differ in wrapping format. Gzip adds a file header (magic bytes 1f8b), timestamp, original filename, and CRC32 checksum around the compressed data, making it more broadly compatible. Deflate is the raw compressed data stream without headers, slightly smaller. We recommend gzip for maximum compatibility — every browser and HTTP server supports it. Choose deflate only when you need the smallest possible output.
❓ What is the difference between Base64 and Hex output formats?
Base64 encodes binary data as printable ASCII characters (A-Z, a-z, 0-9, +, /), expanding every 3 bytes to 4 characters (~1.37x size). Hex (hexadecimal) represents each byte as 2 hex characters (2x size). Base64 is better for transmitting compressed data in text-based protocols (HTTP, JSON), while Hex is better for debugging and visualization. For network transfer use Base64; for development debugging use Hex.
❓ Can I decompress the compressed string back to original text?
Yes. The tool supports bidirectional operation — compressed Base64 or Hex strings can be pasted into the decompression tab with matching format and algorithm settings to restore the original text. Important: decompression must use the same format (Base64↔Base64, Hex↔Hex) and algorithm (gzip↔gzip, deflate↔deflate) as compression. Mismatched settings will produce errors.
❓ Is it safe to compress data in the browser? Does the data leave my device?
Absolutely safe. This tool uses pako.js (a pure JavaScript zlib implementation) to perform all compression and decompression locally in your browser. Your text data is never sent to any server via network requests. All computation happens in your browser's memory, and data disappears when you refresh the page. This ensures complete privacy for sensitive data like API keys, logs, and configuration files.