CRC32 Calculator
Calculate the CRC-32 checksum (IEEE 802.3) of text in hexadecimal and decimal. The same algorithm used by zlib, PNG and ZIP files.
Last reviewed by the Radiatus Cloud team
Compute the CRC-32 checksum of text, the same algorithm used by ZIP, PNG and zlib.
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Calculate a CRC-32 checksum
CRC-32 is a cyclic redundancy check that produces a thirty-two-bit checksum from data, used to detect accidental changes such as transmission or storage errors. This calculator implements the standard IEEE 802.3 variant with the reversed polynomial 0xEDB88320, which is exactly the algorithm used by zlib, the ZIP archive format, PNG images and Ethernet frames. It encodes your text as UTF-8 bytes and returns the checksum in both hexadecimal and decimal.
Because the algorithm and polynomial match the widely used standard, the value produced here will agree with CRC-32 functions in programming languages and file formats.
What CRC-32 is for
CRC-32 is designed to catch random errors, not to resist deliberate tampering, so it is a fast integrity check rather than a cryptographic hash. Developers use it to verify that a file transferred correctly, to deduplicate data, and to validate the integrity of archive members. The same value appears in the central directory of ZIP files and in the chunks of PNG images.
If you need to detect malicious modification, a cryptographic hash such as SHA-256 is the right choice, since CRC-32 can be forged intentionally. For error detection, however, CRC-32 is efficient and effective. All calculation happens locally in your browser.
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Frequently Asked Questions
What CRC-32 variant does this use?
It uses the standard IEEE 802.3 variant with the reversed polynomial 0xEDB88320, the same one used by zlib, ZIP, PNG and Ethernet.
Will the result match my programming language?
Yes. Languages that implement standard CRC-32, such as Python\'s zlib.crc32, produce the same value for the same UTF-8 bytes.
Is CRC-32 a secure hash?
No. It detects accidental errors but can be deliberately forged, so it is not suitable for security. Use SHA-256 for tamper detection.
How is the text encoded before hashing?
The text is encoded as UTF-8 bytes first, so characters beyond ASCII are handled consistently with other standard implementations.
Why are there hex and decimal outputs?
Different tools display CRC-32 in different bases. The hexadecimal form is common in file formats, while decimal is often used in code.
Privacy & Security
Everything runs in your browser; nothing is uploaded.
How to Use
Enter text to compute its CRC-32 checksum in hex and decimal.
Disclaimer: This tool is provided "as is" without warranty of any kind. Results are for educational and utility purposes.
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