CRC32 Checksum.
Compute the CRC-32 of any text — the same checksum used inside zip, gzip, and PNG files — shown as both hex and an unsigned decimal, updating as you type. CRC-32 is for detecting accidental corruption, not for security. Everything runs in your browser.
What CRC-32 is for.
A cyclic redundancy check treats your data as a big binary number and divides it by a fixed "polynomial," keeping the remainder. The standard CRC-32 (polynomial 0xEDB88320 in its reflected form) is the one baked into Ethernet frames, zip entries, gzip streams, and PNG chunks. Flip a single bit anywhere and the checksum almost certainly changes — which is exactly what it's built to catch.
It is not a security hash. CRC-32 is fast and great at spotting accidental corruption, but it's trivial to craft different inputs with the same CRC on purpose. For integrity against tampering, use SHA-256; for passwords, a slow hash. CRC is the smoke detector, not the lock.
This tool encodes your text as UTF-8 before checksumming, so it matches what a file containing those exact bytes would produce. Nothing is uploaded.