hashsum

Compute and verify file checksums with one consistent interface on every OS. Supports MD5, SHA-1, SHA-256, and SHA-512. Zero dependencies.

No more remembering sha256sum (Linux) vs shasum -a 256 (macOS) vs certutil -hashfile / Get-FileHash (Windows) — all of which print different formats.

Install

npm install -g hashsum

Or without installing:

npx hashsum file.zip

Usage

hashsum file.zip                    # SHA-256 (default)
hashsum *.iso -a sha512             # SHA-512 of several files
hashsum dist/* --save              # Write sha256sums.txt
hashsum -c sha256sums.txt          # Verify files against the list
hashsum --string "hello" -a md5    # Hash a literal string

Output Format

Matches sha256sum, so the files are interoperable:

$ hashsum archive.tar.gz
9f86d081884c7d659a2feaa0c55ad015a3bf4f1b2b0b822cd15d6c15b0f00a08  archive.tar.gz

Verify Downloads

Generate a checksum list:

hashsum *.iso -a sha256 --save     # → sha256sums.txt

Verify later (the algorithm is auto-detected from each hash's length):

$ hashsum -c sha256sums.txt

hashsum  verifying 3 file(s) from sha256sums.txt

  ✓ OK  ubuntu.iso
  ✗ FAILED  corrupted.iso
  ? MISSING  deleted.iso

  1 OK  ·  1 failed  ·  1 missing

Exit code is 1 if any file fails or is missing — so it works in CI and scripts.

Supported Algorithms

| Algorithm | Hash length | Notes | |---|---|---| | md5 | 32 hex | Fast, not for security | | sha1 | 40 hex | Legacy | | sha256 | 64 hex | Default — the modern standard | | sha512 | 128 hex | Stronger / faster on 64-bit |

When verifying with -c, the algorithm is inferred from each hash's length, so a mixed file works.

Options

| Flag | Description | |---|---| | -a, --algo <name> | md5 | sha1 | sha256 | sha512 | | -c, --check <file> | Verify files listed in a checksums file | | --string <text> | Hash a string instead of a file | | --save | Write <algo>sums.txt | | --json | JSON output | | --quiet | Print only the hash / exit code |

License

MIT

Keywords

checksum · sha256 · md5 · file hash · sha256sum windows · verify checksum · sha512 · integrity check · cross-platform · zero dependencies

Built to solve, shared to help — Rushabh Shah 🛠️✨

One of 40+ zero-dependency developer CLI tools — no node_modules, ever.