Choose one file
The 100 MiB bound is checked before bytes are read.
Private SHA-2 file utility
Calculate file checksums without uploading the file
HashCheck reads one bounded file inside an isolated no-network browser capsule, calculates three standard SHA-2 digests and compares one optional expected hexadecimal value. A match means byte equality only, never trust or safety.
No account · no upload · no file history · 100 MiB bound
Three explicit steps
Choose, calculate, compare
Calculate locally
Web Crypto produces SHA-256, SHA-384 and SHA-512 sequentially.
Compare exact text
Paste one continuous published SHA-2 value; no prefix or spaces are repaired.
Byte-level comparison
Useful when a trusted source publishes SHA-2
- Compare a completed download with the exact digest published for that version.
- Confirm that a copied or transferred file still has identical bytes.
- Generate reproducible SHA-2 fixtures for tests and documentation.
Private by construction
Calculate the digest in this browser
Choose one file, inspect all three outputs and compare only with an independently trusted value.