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Data Decompressor

Decompress gzip, deflate, brotli or Zstandard data from a file or pasted Base64 and read the result as text or download it. Detects the format from the magic bytes where possible, with a manual override.

Everything runs locally in your browser. Your data never leaves your device.

Input

Drop a compressed file here

.gz, .zz, .deflate, .br, .zst or anything else. Click to choose one.

Format

gzip, Zstandard and zlib announce themselves with magic bytes, so auto detect recognizes them instantly. Brotli and raw deflate have no signature at all, they can only be found by trying.

Next steps

Send this tool's output straight into another tool.

Data Compressor

Compress text or a file with gzip, deflate, brotli or Zstandard and see the size before and after, the compression ratio and how long it took. One click tries every method and recommends the smallest result.

devcompress

Text Case Converter

Convert text into every case at once: title case in the APA, AP, Chicago, MLA, Bluebook, AMA and NYT styles, sentence case, upper, lower, camelCase, snake_case, kebab-case and more.

textconverter

Word & Character Counter

Count words, characters, sentences, paragraphs, lines and more as you type, with estimated reading and speaking time.

text

Dedupe Lines

Remove duplicate lines from a list or text, keeping the first occurrence. Optionally ignore case and whitespace, or drop blank lines too.

textdev

Find and Replace

Replace text in two modes: plain find and replace all, or regular expressions with flag controls and capture group references like $1.

textdev

Text Diff

Compare two texts and see every added, removed and changed line highlighted, side by side or inline, with the changed words marked within each line. Ignore case, whitespace or blank lines, read a summary of how much changed, and export the result as a unified diff.

textdev

UUID Decoder

Paste a UUID to see what it carries: version, variant, and for time-based versions the exact timestamp, clock sequence and node. Also shows the raw bytes, the 128-bit integer and the URN form.

devuuid

Base64 Encoder & Decoder

Decode Base64 to text or encode text to Base64. Paste into the top box, read the result below, and flip the direction with one click. Handles Unicode correctly, reads URL-safe Base64, and shows binary payloads as a hex dump you can download.

devconvertertext

Number Base Converter

Convert numbers between binary, octal, decimal, hexadecimal and any base up to 36. Type into any field and the others update as you go. Handles huge integers without losing precision and accepts 0x, 0b and 0o prefixes.

devconvertercalculator

About the Data Decompressor Tool

This tool decompresses gzip, deflate (zlib), raw deflate, Brotli and Zstandard data from a dropped file or a pasted Base64 string. It detects the format from the magic bytes and the file extension where possible, with a manual override for the formats that carry no signature.

Results that decode as UTF-8 text appear ready to copy. Binary results are recognized from their magic bytes. Images, PDFs, audio and video appear as a preview, everything else as a hex view, and either way the file can be downloaded. Data compressed with the Data Compressor can be forwarded here with one click.

What you can do

  • Decompress .gz, .zz, .deflate, .br and .zst files.
  • Decode Base64 and decompress it in one step.
  • Detect the compression format from the magic bytes automatically.
  • Read decompressed text directly, preview decompressed images and media, or download binary results.
  • See the compressed and decompressed sizes and the expansion factor.

How to use the Data Decompressor

  1. 1Drop a compressed file, or paste the Base64 of the compressed data.
  2. 2Keep Auto detect, or pick the format if you know it.
  3. 3Press Decompress.
  4. 4Copy the text result or download the file.

How detection works

gzip starts with the bytes 1f 8b, Zstandard with 28 b5 2f fd, and zlib has a small structural header the tool can verify. Brotli and raw deflate have no signature at all, so they cannot be recognized from the data alone. Auto detect follows the magic bytes and the file extension first, then simply tries the remaining formats in order and reports what it tried.

When auto detect fails

If every format fails you get the exact error for each attempt instead of a stack trace. A truncated download is the most common cause. If the data came out of a longer pipeline, check that it is not double encoded, Base64 inside Base64 happens more often than you would think.

Credits

Open source does the heavy lifting in this tool. Thank you to:

  • brotli-wasm

    Google's Brotli compression, compiled to WebAssembly.

  • zstd-wasm

    A WebAssembly build of Zstandard, the fast modern compression format.

Everything this site builds on is listed on the credits page.

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Decode Base64 to text or encode text to Base64. Paste into the top box, read the result below, and flip the direction with one click. Handles Unicode correctly, reads URL-safe Base64, and shows binary payloads as a hex dump you can download.

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Bcrypt & Argon2 Generator

Hash a password with bcrypt or Argon2 and verify a password against an existing hash. Tune the cost factor, memory, iterations and parallelism, see how long the hash takes, and read the parsed parts of any hash you paste.

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