Compute SHA-1 digests

Compute a legacy SHA-1 digest for compatibility or file fingerprinting.

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ToolSHA-1 Hash
Input
Output
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Preview

How it works

Bytes are padded with a length field and processed in 512-bit blocks through 80 rounds, producing five 32-bit words and a 160-bit digest. The result is deterministic but not suitable for new collision-sensitive security uses.

  • SHA-1 remains for legacy interoperability.
  • Collision attacks limit new security use.

Worked example

Simple Hash
Generate the SHA-1 digest of a short string
Input
											hello
Output
												aaf4c61ddcc5e8a2dabede0f3b482cd9aea9434d

When to use this

Legacy Git objects, compatibility checksums, and digest migrations use SHA-1.

Edge cases

  • Crafted files can share a collision.
  • One byte changes the digest unpredictably.
  • A hash does not hide or recover input.

References