SHA1 Generator
Generate SHA-1 hashes from any text — instant SHA-1 hash calculation in your browser.
SHA-1 is deprecated for cryptographic use. Use SHA-256 or stronger for security-sensitive applications.
About SHA-1
A cryptographic hash function takes an input of any length and produces a fixed-length output (digest) that uniquely represents the input. Even a single character change produces a completely different hash — this is called the avalanche effect. Hash functions are one-way: you cannot reverse a hash to get the original input.
SHA-1 is used for data integrity verification (checksums for file downloads), digital signatures, certificate generation, and (for SHA-256/SHA-512) password hashing when combined with a salt. This tool computes hashes in your browser using the Web Crypto API — no data is sent to any server.
FAQ
Can I use SHA-1 to store passwords?
No. MD5 and SHA-1 are broken for security use and all SHA variants are too fast for password hashing — attackers can try billions per second. Use bcrypt, Argon2, or scrypt for password storage — these are deliberately slow algorithms designed for this purpose.
What is the difference between encoding and hashing?
Encoding (Base64, URL encoding) is reversible — you can recover the original data. Hashing is one-way — you cannot recover the input from the hash. Use encoding when you need to store and retrieve data. Use hashing when you only need to verify data without storing it.