Free SHA-1 Hash Generator

No, use SHA-256 or SHA-3 for new projects. SHA-1 is deprecated for security purposes due to demonstrated collision attacks. Only use SHA-1 for legacy compatibility.

Git adopted SHA-1 in 2005 when it was standard. The collision attack requires significant resources and crafted inputs unlikely to occur naturally. Git is transitioning to SHA-256 for new repositories.

SHA-1 produces 160-bit hashes (40 hex chars) versus MD5's 128-bit (32 hex chars). SHA-1 is slower but was more secure. Both are now deprecated for cryptographic use; use SHA-256 instead.

SHAttered was the first practical SHA-1 collision, demonstrated in 2017 by Google and CWI Amsterdam. They created two different PDF files with identical SHA-1 hashes, proving the algorithm is broken.

No, hash functions are one-way. You cannot mathematically reverse a hash to get the original input. However, weak inputs like common passwords can be found through rainbow tables or brute force.

Yes, SHA-1 is faster than SHA-256 per byte of input. However, this speed advantage is negligible for most applications and not worth the security tradeoff.