SHA-1 Hash Generator
Get the SHA-1 hash of text or a file in an instant. Type or paste text and the 160-bit hash, 40 hex characters long, updates as you type; files are hashed without being uploaded.
How to generate an SHA-1 hash
- 1Type or paste text, or switch to “A file” and choose one.
- 2Read the SHA-1 hash below.
- 3Copy it, in lowercase or uppercase.
What SHA-1 is for
SHA-1 identifies objects in Git, appears in older checksums and certificates, and is used by many APIs and legacy systems that predate SHA-2.
Security
SHA-1 collisions have been produced in practice since 2017, so it's no longer safe for signatures or certificates. Prefer SHA-256 for anything new.
Text or files
Hash text as you type, encoded as UTF-8, or choose a file up to 2 GB. Files are read in your browser and never uploaded, so it's safe for private documents.
Frequently asked questions
- Is anything sent to a server?
- No. Everything is computed in your browser and nothing leaves your device.
- What does an SHA-1 hash look like?
- Forty hex characters. The SHA-1 of “hello” is aaf4c61ddcc5e8a2dabede0f3b482cd9aea9434d.
- Can a hash be reversed?
- No. A hash is a one-way fingerprint; the only way back is guessing inputs until one matches, which is why short or common inputs are easy to look up.