Hash Generator

Free hash generator: create SHA-1, SHA-256, SHA-384, and SHA-512 hashes from any text. Uses the Web Crypto API, runs in your browser.

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How hash generator works

A hash function takes any input and produces a fixed-size string of characters (the hash) that uniquely identifies the input. Even a tiny change to the input produces a completely different hash. This makes hashes ideal for verifying data integrity, storing passwords, and creating digital signatures.

This generator uses the Web Crypto API (crypto.subtle.digest), which provides cryptographically secure hashing. It supports SHA-1 (160 bits), SHA-256 (256 bits), SHA-384 (384 bits), and SHA-512 (512 bits). SHA-256 is the most commonly used today; SHA-1 is considered weak for security purposes but is still used in some legacy systems like Git.

All hashing happens in your browser. The text you enter never leaves your device. Note that hashing is one-way: you cannot reverse a hash to get the original text. For password storage, always use a salted slow hash function like bcrypt or argon2 instead of plain SHA.

Frequently asked questions

What is a hash?
A hash is a fixed-length string produced by running data through a hash function. The same input always produces the same hash, but different inputs produce different hashes. Hashes are used for integrity verification and digital signatures.
Which hash algorithm should I use?
SHA-256 is the standard for most purposes today. SHA-1 is considered weak and should not be used for security. SHA-512 provides more security but produces longer hashes. For password storage, use bcrypt or argon2 instead.
Can I reverse a hash to get the original text?
No. Hashing is a one-way function. You cannot derive the input from the hash. This is by design, for security. You can only verify that a given input produces the expected hash.
Is my text sent to a server?
No. All hashing happens in your browser using the built-in Web Crypto API. Your text never leaves your device, so it is safe for sensitive data.

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