Important
SHA-1 is cryptographically broken for collision resistance. Do not use it for certificates, signatures, new integrity designs or password storage.
How to use this sha-1 hash generator
- Confirm the legacy system explicitly requires SHA-1.
- Enter the exact UTF-8 text and run the generator.
- Copy the 40-character result without treating it as collision-secure.
SHA-1 is a legacy digest
SHA-1 returns 160 bits, usually written as 40 hexadecimal characters. Practical collision attacks have broken its collision resistance, so this page exists for compatibility—not endorsement.
| Use | Decision |
|---|---|
| Legacy checksum field | Only when the format requires SHA-1 |
| New signatures or certificates | Do not use SHA-1 |
| Password storage | Use a slow salted password hash |
Worked example
The UTF-8 text hello produces aaf4c61ddcc5e8a2dabede0f3b482cd9aea9434d. Matching that value proves only that the bytes produced the same SHA-1 digest; it does not make SHA-1 collision-safe.
SHA-1 questions
Is SHA-1 broken?
Yes, for collision resistance. It should not secure new systems.
Can SHA-1 still verify a legacy value?
It can reproduce a required legacy digest, subject to the legacy system's risk.
What replaces SHA-1?
Use SHA-256 when a modern general-purpose SHA-2 digest is appropriate.