DEFLATE Compressor
Compress text or data using the raw DEFLATE algorithm and view the output as Base64, Hex, or decimal bytes — entirely in your browser using fflate. Adjust the compression level (0–9) to balance speed vs. output size. Your data never leaves your device and no signup is required.
Output Format
Compression Level
6Balanced — good compression, moderate speed
Input
Any text, JSON, XML, HTML, code, or log data
DEFLATE Output (Base64)
Read-only — copy or download the compressed output
About raw DEFLATE
Raw DEFLATE produces compressed bytes with no GZIP or ZLIB header — useful for developers working with network protocols, custom binary formats, or embedding compressed payloads in code. Use Base64 output to embed in JSON or HTML; use Hex for debugging; download .bin for binary integration.
Why Use Our DEFLATE Compressor?
Instant DEFLATE Compression
Compress any text or data with raw DEFLATE instantly in your browser. Our deflate compressor uses fflate — no upload wait, no server queue, results in milliseconds regardless of input size.
Secure DEFLATE Compressor Online
Your data never leaves your device when you use this deflate compressor. 100% client-side processing via fflate guarantees complete privacy — no server logs, no data transmission, no cloud storage.
DEFLATE Compressor Online — No Installation
Compress data with raw DEFLATE directly in any modern browser with no software downloads, no plugins, and no account required. The deflate compressor works on Windows, macOS, Linux, and mobile.
Three Output Formats — Base64, Hex, Binary
Choose Base64 for embedding in JSON, HTML, or URLs; Hex for debugging and protocol analysis; or decimal bytes for low-level binary integration. Download the raw .bin file for any format.
Common Use Cases for DEFLATE Compressor
API Payload Compression
Compress JSON or XML API payloads with raw DEFLATE and encode as Base64 for embedding in query parameters or request bodies. Reduces wire-transfer size by 60–80% for text-heavy API responses.
Embedding Compressed Data in Code
Use Base64 DEFLATE output to embed compressed configuration, templates, or data blobs directly in JavaScript, Python, or Go source code — a common pattern for self-contained scripts.
Custom Binary Protocol Development
Raw DEFLATE (without GZIP or ZLIB headers) is used in PDF streams, PNG image data, and custom network protocols. Use the .bin download to test your parser or protocol implementation.
Database BLOB Compression
Compress text fields before storing as BLOBs in databases. DEFLATE-compressed Base64 strings are smaller than raw text and can be stored in VARCHAR or TEXT columns without binary column types.
URL State Compression
Compress application state or filter parameters with DEFLATE and encode as Base64 for URL-safe query strings. This is the technique used by tools like Grafana and Kibana for shareable dashboard URLs.
Compression Algorithm Debugging
Use the Hex output to inspect raw DEFLATE byte sequences for debugging compression implementations, verifying protocol compliance, or comparing compression levels and their byte-level output.
Understanding DEFLATE Compression
What is Raw DEFLATE Compression?
DEFLATE is a lossless data compression algorithm that combines LZ77 sliding-window compression with Huffman entropy coding. It is the compression algorithm at the core of GZIP, ZLIB, ZIP, PNG, and PDF — but raw DEFLATE produces compressed bytes without any wrapper header. Our deflate compressoruses fflate's deflateRawSync to produce pure DEFLATE-compressed output that you can view as Base64, Hex, or decimal bytes. This is useful for developers working with custom binary protocols, PDF stream objects, PNG IDAT chunks, or any system that expects raw DEFLATE without a GZIP or ZLIB envelope.
How Our DEFLATE Compressor Works
- 1Input your text or data: Paste any text, JSON, XML, HTML, code, or log data into the input panel — or upload a text file using the Upload button. The character count and byte size update in real time.
- 2Choose output format and compression level: Select Base64 for embedding in code or URLs, Hex for debugging, or decimal bytes for low-level analysis. Set the compression level (0–9) to balance speed vs. output size. All processing happens locally in your browser — your data never leaves your device.
- 3Copy or download the output: The compressed output appears in the right panel. Copy it to clipboard with one click, or download the raw binary as a
.binfile. The stats panel shows original size, compressed size, and exact reduction percentage.
What Gets Compressed
- Repeated byte sequences: LZ77 finds and replaces repeated patterns with back-references — text files with repetitive structure like JSON keys, XML tags, and HTML attributes compress dramatically.
- Huffman entropy coding: After LZ77, Huffman coding assigns shorter bit sequences to more frequent symbols, further reducing the output size beyond what LZ77 alone achieves.
- Compression level control: Level 0 stores data uncompressed (no CPU cost), levels 1–3 use fast compression with less CPU, levels 4–6 are balanced, and levels 7–9 apply maximum compression at the cost of more CPU time.
- No wrapper headers: Unlike GZIP (.gz) or ZLIB, raw DEFLATE output contains only the compressed data stream — no magic bytes, no checksum, no filename. This makes it smaller and suitable for embedding in other formats.
Important Limitations
Raw DEFLATE output cannot be decompressed with standard tools like gunzip or unzip — those expect GZIP or ZIP wrappers respectively. To decompress raw DEFLATE, use inflate in fflate, zlib.inflateRaw() in Node.js, zlib.decompress() in Python with wbits=-15, or inflate() in C with inflateInit2(&strm, -15). If you need a self-contained compressed file that any tool can open, use our GZIP Compressor instead.
Related Tools
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Compare JSON byte size vs MessagePack encoding for any payload — shows exact savings, type-by-type breakdown, and MessagePack hex preview. Free online JSON vs MessagePack comparison.
String Decompressor (GZIP/LZ)
Decompress GZIP+Base64, DEFLATE+Base64, and LZ-String compressed payloads back to readable text — supports all three LZ-String variants. Free online string decompressor.
ZIP File Extractor
Extract files from any ZIP archive client-side — browse contents, preview text files, download individual files or all at once. Free online ZIP extractor, no signup required.
Frequently Asked Questions About DEFLATE Compressor
A deflate compressor compresses data using the raw DEFLATE algorithm — the same algorithm at the core of GZIP, ZIP, and PNG — but without any wrapper header. Our free deflate compressor online uses fflate's deflateRawSync to produce pure compressed bytes that you can view as Base64, Hex, or decimal output. Processing happens entirely in your browser — no server upload required.
All three use the DEFLATE algorithm for compression, but they differ in their wrapper format. Raw DEFLATE is just the compressed data stream with no header. ZLIB wraps DEFLATE with a 2-byte header and Adler-32 checksum. GZIP wraps DEFLATE with a 10-byte header (including filename and timestamp) and a CRC32 checksum. Use raw DEFLATE when you control the container format; use GZIP for standalone compressed files.
Absolutely. Our deflate compressor processes everything locally in your browser using fflate — your data is never uploaded to any server and never leaves your device. This makes it completely safe for confidential source code, API keys, configuration files, and sensitive data payloads.
Yes — 100% free, forever. No signup, no account, no premium tier, no data size limits, and no ads. Use the deflate compressor online as many times as you need for personal projects, professional development, or enterprise use — completely free with no restrictions.
Choose Base64 when you need to embed compressed data in JSON, HTML attributes, URL query parameters, or source code strings — Base64 is ASCII-safe and widely supported. Choose Hex when debugging or inspecting the byte sequence of the compressed output. Choose decimal bytes for low-level binary analysis or when working with tools that expect space-separated byte values.
Level 6 is the default and recommended for most use cases — it provides a good balance between compression ratio and speed. Use levels 1–3 for real-time compression where speed matters more than size. Use levels 7–9 for maximum compression when you need the smallest possible output and CPU time is not a concern. Level 0 stores data uncompressed (useful for testing).
Raw DEFLATE cannot be decompressed with gunzip or unzip — those expect GZIP or ZIP wrappers. To decompress: in Node.js use zlib.inflateRaw(); in Python use zlib.decompress(data, wbits=-15); in fflate use inflateRawSync(); in C use inflateInit2(&strm, -15). If you need a file that standard tools can open, use our GZIP Compressor instead.
Text-based data compresses best: JSON, XML, HTML, CSS, JavaScript, SQL, CSV, log files, and plain text typically achieve 60–80% size reduction. Data with many repeated patterns or long repeated sequences compresses most effectively. Binary files that are already compressed (JPEG, PNG, MP3, ZIP) see minimal or no reduction.
There is no artificial size limit. The practical limit depends on your browser's available memory — most modern browsers handle several hundred MB of text without issues. Very large inputs (100 MB+) may take a few seconds at higher compression levels due to the CPU cost of maximum DEFLATE compression.