Checksum Calculator
Compute every common checksum at once — CRC-32 (ZIP, PNG, Ethernet), Adler-32 (zlib), simple 8-bit sum and XOR (serial protocols, NMEA, firmware), plus MD5, SHA-1 and SHA-256 — for text, raw hex bytes or files.
Paste text (hashed as UTF-8) or hex bytes like 48 65 6C 6C 6F, or drop a file, and all checksums are calculated instantly in your browser. Use CRC-32 or Adler-32 to catch accidental corruption and SHA-256 when you need to detect deliberate tampering.
Zero Server Uploads
Files process in local RAM
Instant WASM Speed
No waiting queues or lags
Unlimited Batching
Convert files without limits
Suggest a Feature or Improvement for Checksum Calculator
Need custom options, higher limits, or extra format support? Let our engineering team know!
How to use Checksum Calculator
- 1Choose Text or Hex bytes, or drop a file.
- 2Enter the data.
- 3Read all checksums side by side.
- 4Copy the one your system expects.
Checksums vs cryptographic hashes
CRC-32 and Adler-32 are fast error-detecting codes. They reliably catch random bit flips, which is why ZIP, PNG, gzip and network protocols use them, but anyone can craft data with a chosen CRC. Cryptographic hashes like SHA-256 are designed so that's infeasible.
The 8-bit sum and XOR checksums are common in embedded protocols (for example the NMEA 0183 GPS sentence checksum is an XOR of the bytes between $ and *).
Matching other tools
CRC-32 here is the IEEE 802.3 polynomial (0xEDB88320 reflected), matching zlib, PHP's crc32() and Python's zlib.crc32(). For verifying downloads, use the File Hash Checker.
Frequently Asked Questions
Which CRC-32 variant is this?
The standard IEEE CRC-32 used by ZIP, PNG, gzip and Ethernet. Other variants (CRC-32C, CRC-32/MPEG-2) give different results.
Can I enter binary data?
Yes — switch to Hex bytes and paste the bytes in hex, with or without spaces, or drop the binary file.
Is my data sent to your server?
No. This tool runs entirely in your browser using the Web Crypto API and JavaScript. Nothing you type or generate is uploaded, logged or stored.
Guides & Tutorials
Related Tools
File Hash Checker
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MD5 Hash Generator
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SHA-256 Hash Generator
Generate SHA-256 hashes of text or files instantly — hex or Base64, with checksum comparison.