Hash Generator

What is a cryptographic hash?

A cryptographic hash function takes any input — a single character, a document, or an entire file — and produces a fixed-length string of hexadecimal characters called a digest. The same input always produces the same hash, but even a tiny change to the input produces a completely different output. This property is called the avalanche effect.

Hash functions are one-way: you cannot reverse-engineer the original input from the hash. This makes them fundamentally different from encryption, which is designed to be reversible with the correct key. Hashing is used for data integrity verification, password storage, digital signatures, and many other security applications.

Hash algorithms supported

• SHA-1: SHA-1 produces a 160-bit hash (40 hex characters). It was once the standard for TLS certificates and Git commits, but cryptographic weaknesses were discovered in 2017. SHA-1 is now deprecated for security use but remains common for non-security checksums.
• SHA-256: SHA-256 produces a 256-bit hash (64 hex characters). It is the most widely used algorithm today, securing TLS connections, Bitcoin transactions, code signing certificates, and software package verification.
• SHA-384: SHA-384 produces a 384-bit hash (96 hex characters). It is a truncated version of SHA-512, commonly used in TLS certificate chains and HMAC constructions where extra security margin is desired.
• SHA-512: SHA-512 produces a 512-bit hash (128 hex characters). It offers the maximum strength in the SHA-2 family and can be faster than SHA-256 on 64-bit processors because it operates on 64-bit words natively.

Common uses for hashing

• Verifying file integrity by comparing checksums after download.
• Storing passwords securely in databases (always with a unique salt per user).
• Generating digital signatures for documents and software packages.
• Cache-busting in web development by appending content hashes to filenames.
• Creating unique content-addressed identifiers in distributed systems.

Hashing vs. encryption

Encryption is reversible — you can decrypt data with the correct key. Hashing is a one-way function — you cannot recover the original text from a hash. This makes hashing ideal for passwords (you only need to verify, not recover) and integrity checks (you only need to detect changes).

Is my text secure?

All hashing uses your browser's built-in Web Crypto API (crypto.subtle). Your text is never transmitted to any server. The Web Crypto API is the same cryptographic engine used by HTTPS, ensuring industrial-strength implementations of every algorithm.

Frequently asked questions

Can two different inputs produce the same hash?

Theoretically yes — this is called a collision. However, for SHA-256, finding a collision requires approximately 2¹²⁸ operations, which is computationally infeasible with current or foreseeable technology. SHA-1 collisions have been demonstrated, which is why it was deprecated.

Which hash algorithm should I use?

For most purposes, SHA-256 is the best choice. It offers strong security, wide compatibility, and excellent performance. Use SHA-512 if you need extra security margin or are working on 64-bit systems where it may be faster. Avoid SHA-1 for any security-sensitive application.