Hash Calculator

Understanding Cryptographic Hash Functions

A cryptographic hash function is a mathematical algorithm that takes an input (or 'message') and returns a fixed-size string of bytes. The output, known as the hash value or digest, is typically a hexadecimal string that appears random. Hash functions are fundamental to modern cryptography and are used in various applications including digital signatures, password storage, and data integrity verification.

Key Properties of Hash Functions

• Deterministic: The same input will always produce the same hash output
• Fast Computation: Hash values can be computed quickly for any given input
• Pre-image Resistance: It should be computationally infeasible to reverse the hash function
• Small Changes, Big Differences: A small change in input should produce a significantly different hash
• Collision Resistance: It should be hard to find two different inputs that produce the same hash

Common Hash Algorithms

• MD5: 128-bit hash, fast but cryptographically broken - use only for checksums
• SHA-1: 160-bit hash, deprecated for security purposes but still used in some legacy systems
• SHA-256: 256-bit hash, part of the SHA-2 family, widely used and considered secure
• SHA-512: 512-bit hash, provides higher security than SHA-256
• SHA3-256/SHA3-512: Part of the SHA-3 family, designed as a modern alternative to SHA-2
• CRC32: 32-bit checksum primarily used for error detection, not for security

This calculator provides a convenient way to generate hashes for text inputs or files, compare different algorithms, and understand their security characteristics and performance characteristics.