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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.

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

Input

Method

6

0 is fastest, 9 compresses hardest.

Add some text or a file first.

Next steps

Send this tool's output straight into another tool.

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.

devcompress

Hash Generator

Hash text or a file with MD5, SHA-1, SHA-256, SHA-512, SHA-3, BLAKE2, BLAKE3, CRC32 and more, all computed live as you type. Compare against an expected checksum and copy any digest.

devsecurity

Checksum Validator

Verify a checksum online: drop a file, paste the expected checksum and see instantly whether they match. The hash type is detected from the checksum itself, covering MD5, SHA-1, SHA-256, SHA-512, BLAKE3, CRC-32 and more, and sha256sum lines or whole checksum files can be pasted as-is.

devsecurity

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

About the Data Compressor

This tool compresses text or a file with gzip, deflate (zlib), raw deflate, Brotli or Zstandard and shows exactly what you gained: the size before and after, the percentage saved, the compression ratio and how long the codec took.

Not sure which method to pick? One click on Find best method runs all five over your data and recommends the smallest result. You can then forward the output straight to the Data Decompressor to verify the round trip.

What you can do

  • Compress text or any file with gzip, deflate, Brotli or Zstandard.
  • Compare every compression method on the same data and pick the smallest result.
  • Measure the compression ratio and speed of gzip, Brotli and zstd.
  • Download the result with the right extension (.gz, .zz, .deflate, .br or .zst).
  • Copy small results as Base64 for configs, tickets or tests.

How to use the Data Compressor

  1. 1Paste text, or switch to File and drop any file.
  2. 2Pick a method and set its level or quality, or press Find best method to try them all.
  3. 3Read the before and after sizes, the space saved, the ratio and the time taken.
  4. 4Inspect the compressed bytes in the hex view, download the file, or copy it as Base64.

Choosing a method

gzip is the safe default, every tool and server understands it. Brotli usually produces the smallest output for text and web assets but takes longer at high quality. Zstandard gets close to Brotli while compressing and decompressing much faster, which is why it is popular for build artifacts and backups. deflate (zlib) and raw deflate are the same algorithm gzip uses, just with a lighter or no container, for when a spec asks for exactly that framing.

How Find best method works

Find best method runs every codec over the same input at its strongest practical setting: level 9 for gzip and the deflate variants, quality 11 for Brotli and level 19 for Zstandard. The results are sorted by size, the smallest is highlighted and adopted as the active result, and each row reports its timing so you can trade a few percent of size against speed.

When compression makes data bigger

Already compressed data such as JPEG photos, video or ZIP archives has little redundancy left, so a second pass often grows it slightly. The tool reports that honestly as a negative saving instead of hiding it. Random or encrypted data behaves the same way.

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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.

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Shrink an SVG with SVGO. Paste the markup or drop a file, toggle every optimizer plugin individually, set the numeric precision and multipass, and compare the size before and after. Copy the result or download it as a file.

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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.

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Checksum Validator

Verify a checksum online: drop a file, paste the expected checksum and see instantly whether they match. The hash type is detected from the checksum itself, covering MD5, SHA-1, SHA-256, SHA-512, BLAKE3, CRC-32 and more, and sha256sum lines or whole checksum files can be pasted as-is.

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Clipboard Inspector

See what your clipboard really holds. One press lists every format on it, from plain text and HTML to Excel tables and images, each with its type, size and a preview. Pasting works too, and can reveal even more formats.

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Color Contrast Checker

Check two colors against the WCAG contrast rules. Type or pick a text and a background color, read the contrast ratio, see which AA and AAA checks pass, preview real text at the sizes WCAG distinguishes, and get suggested fixes when a check fails.

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