SHA-1 Hash Generator Online — Legacy SHA1 Checksum Tool
All 4 algorithms simultaneously · HMAC mode · File hashing · Compare · Batch · 100% browser-side
Type text → get all 4 hashes instantly
MD5 · SHA-1 · SHA-256 · SHA-512 · Real-time
Generate SHA-1 hashes for legacy system compatibility. SHA-1 is deprecated for security but still used for Git object IDs, legacy checksums, and non-security deduplication. Produces a 160-bit (40 hex char) hash.
What is a Hash Function?
A hash function converts any input — text, password, file — into a fixed-length string of hexadecimal characters. The same input always produces the same hash, but even a single character change produces a completely different hash. Hashes are one-way — you cannot reverse them to recover the original input.
MD5 vs SHA-1 vs SHA-256 vs SHA-512
MD5 (128-bit, 32 hex chars) is fast and widely used for non-security checksums but is cryptographically broken. SHA-1 (160-bit, 40 hex chars) is deprecated for security use since 2017. SHA-256 (256-bit, 64 hex chars) is the current industry standard — used in SSL certificates, Bitcoin, and code signing. SHA-512 (512-bit, 128 hex chars) offers maximum security for highly sensitive applications.
Frequently Asked Questions
What is SHA-1?
SHA-1 (Secure Hash Algorithm 1) is a 160-bit hash producing a 40-character hex string. Developed by the NSA in 1993, it was the dominant hash until 2017 when SHA-256 took over.
Is SHA-1 still safe?
SHA-1 is deprecated for security use since 2017 when Google demonstrated a practical collision attack (SHAttered). All major browsers and CAs no longer accept SHA-1 certificates. Use SHA-256 for security.
Where is SHA-1 still used?
SHA-1 is still used in Git for object IDs (though Git is migrating to SHA-256), legacy software checksums, older protocols like SVN and CVS, and systems that cannot be upgraded.
SHA-1 vs MD5 — which is better?
SHA-1 is stronger than MD5 — 160 bits vs 128 bits and different vulnerabilities. But both are considered cryptographically broken for security purposes. Both are fine for non-security checksums.
Why does Git use SHA-1?
Git uses SHA-1 for its object database (commits, blobs, trees). Git does not use SHA-1 for security but for content addressing — the hash identifies content. Git is working on migrating to SHA-256 in newer versions.