SHA1 Hash

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Output

Options

Output hash as:

What is a SHA1 Hash?

SHA-1, or Secure Hash Algorithm 1, is a cryptographic hash function designed by the National Security Agency (NSA) and published by the National Institute of Standards and Technology (NIST) in 1993. It produces a fixed-size 160-bit (20-byte) hash value from input data of varying lengths and was initially considered secure for a wide range of applications, including digital signatures and data integrity verification. However, as computing power advanced, researchers discovered vulnerabilities in SHA-1 that made it susceptible to collision attacks, where two different inputs could produce the same hash value. Due to these vulnerabilities, SHA-1 has been gradually phased out from secure applications, and organizations have been strongly encouraged to transition to more secure alternatives such as SHA-256 and SHA-512. Despite its security shortcomings, SHA-1 is still occasionally used for non-cryptographic purposes like checksums and data verification where security is not a primary concern.