Checksum Calculator

Hash text or files locally, verify published checksums and checksum manifests, compare content fingerprints, and inspect exactly which bytes were hashed. Cryptographic and fast corruption-detection algorithms live side by side—with clear security labels.

100% local · files never uploaded

Input bytes

Local only

Input mode

Text / bytes

Interpret as

Line endings

Ready. SHA-256 is usually the best default for published file integrity checks.

Checksums & hashes

— bytes

Security note: CRC32/CRC32C/Adler-32 detect accidental corruption. MD5 and SHA-1 are legacy fingerprints and should not establish authenticity. Prefer SHA-256 or stronger when a trusted publisher provides it.

Expected checksum

Paste published digest

Paste a checksum and calculate the current input first.

Auto-detection

Digest length

—

Possible algorithm(s)

—

Normalization

Hex comparison is case-insensitive; optional 0x prefix is ignored.

Checksum manifest

SHA256SUMS / BSD-style manifest

Select matching local files

Ambiguous 8-hex checksums require an explicit algorithm name (CRC32, CRC32C, or ADLER32) in BSD style.

Verification results

Line	File	Algorithm	Status	Computed
No manifest verified yet.

Content A

Text

Content B

Text

Digest comparison

Choose the right algorithm

SHA-256 / SHA-384 / SHA-512
Use when verifying a digest supplied through a trusted channel.

SHA-1 / MD5
Useful only when compatibility demands them. Collision resistance is broken or deprecated.

CRC32 / CRC32C / Adler-32
Fast error-detection checksums, not cryptographic authenticity mechanisms.

Exact-byte discipline

A checksum belongs to bytes, not to what text “looks like.” Encoding, Unicode, BOMs and line endings can change a digest. The byte controls in this tool make those transformations explicit rather than silently changing your input.