PHP 8 reference · String Functions

PHP sha1() Function

Calculate the SHA-1 hash of a string as 40 hex characters. Weak for security; prefer hash("sha256", ...).

PHP 8 Since 4.3

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Syntax

sha1(string $string, bool $binary = false): string

Parameter	Description
`string`	The input string.
`binary` optional	`true` returns the raw 20-byte digest. Default: `false`

The hash as a hex string.

Hash a stringTry it yourself

<?php
echo sha1("hello"), "\n";

Output

aaf4c61ddcc5e8a2dabede0f3b482cd9aea9434d

Prefer SHA-256Try it yourself

<?php
echo hash("sha256", "hello"), "\n"; // the stronger choice

Output

2cf24dba5fb0a30e26e83b2ac5b9e29e1b161e5c1fa7425e73043362938b9824

Version	Change
PHP 4.3	Added

md5() · Calculate the MD5 hash of a string as 32 hex characters. Fine for checksums and cache keys, never for passwords.
hash() · Hash a string with the algorithm you choose, such as sha256, sha512, crc32b or xxh3. Returns a hex string.
PHP Strings · tutorial