SHA1 Generator
Generate SHA1 hash
Frequently Asked Questions
What is SHA-1?
SHA-1 (Secure Hash Algorithm 1) produces a 160-bit (40-character hexadecimal) hash. "Hello" always produces f7ff9e8b7bb2e09b70935a5d785e0cc5d9d0abf0. It was widely used for digital signatures and certificates until collision attacks were demonstrated in 2017.
Is SHA-1 still secure?
SHA-1 is considered cryptographically weak. Google demonstrated a practical collision attack (SHAttered) in 2017. Major browsers and certificate authorities have deprecated SHA-1. Use SHA-256 or SHA-3 for security-sensitive applications.
Where is SHA-1 still used?
Git uses SHA-1 for commit hashes (migrating to SHA-256). Some legacy systems still use SHA-1 for checksums. It remains in use for non-security purposes where collision resistance is not critical, like data deduplication.
Can I hash a file with SHA-1?
Yes. Upload any file to compute its SHA-1 hash. This is used to verify file integrity — compare the hash with the expected value. For security-critical verification, prefer SHA-256 checksums instead.
How does SHA-1 compare to MD5?
SHA-1 produces a longer hash (160 bits vs 128 bits) and is more collision-resistant than MD5, but both are now considered broken for security. SHA-1 is slower than MD5. For modern applications, use SHA-256 minimum.