Hash Generator

Generate cryptographic hashes for any text. Supports MD5, SHA-1, SHA-256, SHA-512, and bcrypt.

Text to Hash

0 characters • Press Enter to generate

About Hash Algorithms

MD5 & SHA-1

Legacy algorithms. Not recommended for security purposes due to known vulnerabilities. Still useful for checksums and non-security applications.

SHA-256 & SHA-512

Modern, secure hash algorithms from the SHA-2 family. Recommended for most applications including digital signatures and integrity verification.

bcrypt

Password hashing algorithm with built-in salting and configurable cost factor. Specifically designed for securely storing passwords. Each hash includes a unique salt.

Command Line

$ curl -X POST https://dnsx.dev/hash -H "Content-Type: application/json" \

-d '{"text":"hello world"}'

$ curl -X POST https://dnsx.dev/hash -d '{"text":"test","algorithms":["sha256"]}'

Understanding Cryptographic Hashing

Cryptographic hash functions are fundamental building blocks of modern security. They transform any input -- whether a single character or an entire file -- into a fixed-size string of characters that serves as a unique digital fingerprint. This process is one-way: given a hash output, it is computationally infeasible to determine the original input.

Hash functions are used everywhere in computing: verifying file downloads, storing passwords securely, ensuring data integrity in databases, creating digital signatures, and powering blockchain technology. Understanding the differences between hash algorithms helps you choose the right one for your specific use case.

Hash Algorithms Compared

MD5 (128-bit)

Fast but broken for security. Vulnerable to collision attacks since 2004. Use only for non-security checksums and legacy compatibility.

SHA-1 (160-bit)

Deprecated for security since 2017 when Google demonstrated a practical collision (SHAttered). Avoid for new applications.

SHA-256 (256-bit)

The recommended general-purpose hash. Used in TLS, Bitcoin, Git, and digital signatures. No known vulnerabilities.

SHA-512 (512-bit)

Larger output for higher security margins. Actually faster than SHA-256 on 64-bit systems due to native 64-bit operations.

bcrypt (adaptive)

Purpose-built for password hashing. Includes salt and configurable cost factor. Deliberately slow to prevent brute-force attacks. The only algorithm here designed specifically for storing passwords.

Frequently Asked Questions

What is a cryptographic hash?▼

A cryptographic hash function takes any input data and produces a fixed-size output (the "hash" or "digest") that appears random. Key properties include: determinism (same input always produces the same output), one-way computation (you cannot reverse a hash to find the original input), avalanche effect (a tiny change in input completely changes the output), and collision resistance (it is extremely difficult to find two different inputs that produce the same hash).

Is MD5 still safe to use?▼

MD5 is no longer considered safe for security purposes. Researchers demonstrated practical collision attacks in 2004, meaning it is possible to create two different inputs that produce the same MD5 hash. MD5 should never be used for password hashing, digital signatures, or certificate verification. However, MD5 is still acceptable for non-security uses like checksums for file integrity verification (where an attacker is not actively trying to create collisions) or as a fast hash for hash tables.

What is bcrypt?▼

bcrypt is a password hashing algorithm designed specifically for securely storing passwords. Unlike general-purpose hash functions like SHA-256, bcrypt includes three critical features: a built-in salt (random data added to each password before hashing, preventing rainbow table attacks), a configurable cost factor (controls how computationally expensive the hash is to compute, allowing it to scale with hardware improvements), and deliberate slowness (designed to be slow to compute, making brute-force attacks impractical).

What is SHA-256 used for?▼

SHA-256 (Secure Hash Algorithm 256-bit) is one of the most widely used cryptographic hash functions. It is used in TLS/SSL certificates to verify website authenticity, Bitcoin mining and blockchain verification, digital signatures and code signing, file integrity verification (checksums), HMAC-based authentication tokens, and Git version control (for commit identification). SHA-256 is part of the SHA-2 family and has no known practical vulnerabilities.