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Hash Generator

Generate MD5, SHA-1, SHA-256, and SHA-512 cryptographic hashes from any text. Uses the browser's native Web Crypto API — fast, secure, and completely offline. Your data never leaves your device.

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Hash Results

MD5128-bitLegacy

Hash will appear here…

SHA-1160-bitWeak

Hash will appear here…

SHA-256256-bitSecure

Hash will appear here…

SHA-512512-bitStrong

Hash will appear here…

Security note: MD5 and SHA-1 are cryptographically broken and should not be used for security purposes. Use SHA-256 or SHA-512 for password hashing (with a salt), file integrity checks, and digital signatures.

How to Use the Hash Generator

Type or paste any text into the input box and click Generate Hashes (or press Enter). The tool instantly computes all four hashes in parallel and displays them with copy buttons.

Hash Algorithm Comparison

AlgorithmOutput LengthSecurityUse Case
MD5128-bit (32 hex chars)BrokenLegacy checksums, non-security deduplication only
SHA-1160-bit (40 hex chars)WeakLegacy systems, Git object IDs (non-security)
SHA-256256-bit (64 hex chars)SecureFile integrity, API signatures, HMAC, certificates
SHA-512512-bit (128 hex chars)StrongHigh-security applications, large data integrity

Common Use Cases for Hash Generation

File Integrity Verification

Software download pages publish SHA-256 hashes alongside download links. After downloading, generate the hash of the file and compare it to the published value. A mismatch indicates corruption or tampering.

API Request Signing

Many APIs use HMAC-SHA256 to sign requests. The client computes a hash of the request body + timestamp + secret key and includes it as a header. The server recomputes and compares to authenticate the request.

Content Deduplication

Generate SHA-256 hashes of files or text blobs to detect duplicates without storing the full content. Two identical inputs always produce identical hashes.

Cache Busting

Hash the content of static assets (CSS, JS, images) and include the hash in the filename or URL query string. This ensures browsers fetch new versions when content changes.

Why You Should Never Hash Passwords with SHA-256

SHA-256 and SHA-512 are designed to be fast. A modern GPU can compute billions of SHA-256 hashes per second, which means an attacker with a database of stolen hashes can try every common password in seconds using a dictionary or brute-force attack.

Password hashing algorithms like bcrypt, Argon2, and scrypt are intentionally slow and include a unique salt per password. They make brute-forcing computationally impractical even with powerful hardware. Always use a dedicated password hashing library for storing user credentials.

Technical Implementation

This tool uses two computation methods:

  • SHA-1, SHA-256, SHA-512: Computed via the window.crypto.subtle.digest() API — a native browser cryptography API that runs in a secure context and produces cryptographically verified results.
  • MD5: Computed via a pure JavaScript implementation since the Web Crypto API does not support MD5 (it is deprecated for cryptographic use). The implementation follows RFC 1321.

Frequently Asked Questions

What is a hash function and what is it used for?

A cryptographic hash function takes an input (a string or file) and produces a fixed-length output called a hash or digest. Hashes are deterministic (same input always produces same output) and one-way (you cannot reverse a hash to get the original input). Common uses include: verifying file integrity (compare downloaded file hash to the published hash), storing passwords securely (store hash, not plaintext), generating unique identifiers, digital signatures, and checksums.

Which hash algorithm should I use — MD5, SHA-1, SHA-256, or SHA-512?

MD5 and SHA-1 are cryptographically broken and should NOT be used for any security-sensitive purpose. Both can be reverse-engineered using rainbow tables or collision attacks. Use SHA-256 for general security purposes (file integrity, API signatures, HMAC). Use SHA-512 when you need maximum collision resistance, or for password hashing in older systems. For password storage specifically, use bcrypt, Argon2, or scrypt with a salt — never SHA-256/512 alone, as they are too fast for passwords.

Does this tool send my text to a server?

No. All hash generation happens entirely in your browser. SHA-1, SHA-256, and SHA-512 are computed using the Web Crypto API (window.crypto.subtle.digest), a native browser API with no network access. MD5 is computed using a pure JavaScript implementation. Your input never leaves your device.

Why do MD5 hashes of the same text always match but small changes produce completely different hashes?

This is the avalanche effect — a fundamental property of cryptographic hash functions. Even a single bit change in the input completely changes the output hash, making it impossible to deduce what changed. This is by design: it makes it computationally infeasible to work backwards from a hash to find the original input, and ensures that two slightly different inputs produce very different hashes.

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