crc32 / crc16 · local only
CRC Calculator
Calculate CRC32 and CRC16 checksums for text and files — the error-detection codes used by ZIP, PNG, Ethernet and embedded protocols.
All files are processed locally in your browser — your data never leaves your device.
About CRC checksums
A CRC (Cyclic Redundancy Check) is a fast error-detecting code built on polynomial division. Unlike cryptographic hashes, CRCs are designed purely to catch accidental changes — flipped bits from a noisy transmission line, a truncated download, a corrupted sector. CRC-32 (the IEEE 802.3 polynomial computed here) is the checksum inside ZIP and GZIP archives, PNG image chunks, and Ethernet frames. CRC-16 (the ARC/IBM variant) appears in Modbus, XMODEM and many embedded and serial protocols.
This CRC calculator computes both variants from typed text or a dropped file. File input is streamed chunk by chunk, so checking the CRC-32 of a large archive is quick and memory-friendly. Results are shown as standard hexadecimal: 8 characters for CRC-32, 4 for CRC-16.
CRC vs. cryptographic hashes
Because a CRC is only 16 or 32 bits and trivially invertible, it offers no protection against deliberate tampering — anyone can craft data matching a target CRC. Use it where speed matters and the threat is random corruption: verifying archive integrity, debugging serial protocols, or matching the CRC values that archive tools report. When you need assurance that a file has not been maliciously modified, use the SHA-256 generator or SHA-512. For hashing many algorithms at once over the same file, try the file checksum calculator.
Also try our: File Checksum Calculator · MD5 Hash Generator · SHA256 Hash Generator