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How to Use CRC32 Checksum Generator

Calculate the CRC32 checksum of any text instantly, matching ZIP, PNG and PHP crc32(). Compare with a known value. Free CRC32 calculator in your browser.

About this tool

CRC32 is a fast 32-bit checksum used to detect accidental changes to data. It is built into ZIP archives, PNG images, Ethernet frames and many file formats. This calculator uses the standard IEEE 802.3 polynomial, the same one as ZIP and PHP's crc32() function, and shows the result as 8 hexadecimal characters.

How to use CRC32 Checksum Generator

  1. Type or paste your text.
  2. Copy the 8-character CRC32 checksum.
  3. Paste an expected value into the compare box to check it.

Worked example

The CRC32 of "The quick brown fox jumps over the lazy dog" is 414fa339.

Is CRC32 a secure hash?

No. It is designed to catch accidental errors like transmission noise, not deliberate tampering, and collisions are easy to create. Use SHA-256 for security.

Why is my CRC32 different from another tool?

There are several CRC-32 variants. This tool uses the common CRC-32/ISO-HDLC (IEEE 802.3) version used by ZIP, PNG and most software, and hashes the text as UTF-8.

How do I get the decimal value?

Convert the hexadecimal result with the Number Base Converter; PHP's crc32() returns the same number as a decimal integer.

Put this guide into practice

Explore Security & Encoding Tools · More practical guides

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