SHA-1 Hash Generator
Generate a SHA-1 message digest from text input. Paste or type text, select Generate hash, and the tool returns the 160-bit digest as 40 lowercase hexadecimal characters.
What is SHA-1?
SHA-1, or Secure Hash Algorithm 1, is a deterministic hash function that maps input text to a 160-bit message digest, normally displayed as 40 lowercase hexadecimal characters.
This tool hashes the text you enter as UTF-8 bytes and writes the resulting SHA-1 digest to the output box without sending the text to a server. Whitespace, punctuation, letter case, line endings, and non-ASCII characters all affect the result, so compare the output only with systems that hash the same text encoding.
SHA-1 is useful when you need to reproduce legacy checksums, compare non-secret text against an existing SHA-1 value, or inspect data formats and protocols that still publish SHA-1 fingerprints. It is not encryption and cannot be decoded back to the original text.
Do not choose SHA-1 for new security-sensitive designs. Practical collision attacks have broken SHA-1's collision resistance, NIST has deprecated it for digital signatures, and modern systems should prefer SHA-256, SHA-512, SHA-3, or a purpose-built password hashing or message authentication construction where those are the actual requirement.
