Free Hash Generator — MD5, SHA-256, SHA-512 Online

Need to hash a string or verify a file checksum? Our free hash generator supports MD5, SHA-1, SHA-256, SHA-384, and SHA-512 — all running in your browser using the Web Crypto API. Your data never leaves your machine.

What is Hashing?

Hashing is a one-way function that converts any input into a fixed-length string of characters. The same input always produces the same hash, but you can't reverse a hash back to the original input. This makes hashing essential for:

• Password storage — store hashes, not plaintext passwords
• File integrity verification — check if a download was corrupted or tampered with
• Digital signatures — sign documents and verify authenticity
• Data deduplication — identify duplicate files by comparing hashes
• Caching — generate cache keys from content

Hash Algorithm Comparison

Which Algorithm Should You Use?

SHA-256 is the default choice for most applications. It's secure, widely supported, and fast enough for any workload. Use MD5 only for non-security checksums (like verifying file integrity where tampering isn't a concern).

Hash Examples

Hashing the string hello world with each algorithm:

MD5:     5eb63bbbe01eeed093cb22bb8f5acdc3
SHA-1:   2aae6c35c94fcfb415dbe95f408b9ce91ee846ed
SHA-256: b94d27b9934d3e08a52e52d7da7dabfac484efe37a5380ee9088f7ace2efcde9
SHA-384: fdbd8e75a67f29f701a4e040385e2e23986303ea10239211af907fcbb83578b3
         e417cb71ce646efd0819dd8c088de1bd
SHA-512: 309ecc489c12d6eb4cc40f50c902f2b4d0ed77ee511a7c7a9bcd3ca86d4cd86f
         989dd35bc5ff499670da34255b45b0cfd830e81f605dcf7dc5542e93ae9cd76f

Notice how even though "hello world" is tiny, every algorithm produces a completely different, fixed-length output. Change a single character and the entire hash changes — this is called the avalanche effect.

Hashing Files

Our tool supports file hashing via drag-and-drop or file picker. Common use cases:

• Verify downloads — compare the hash of your downloaded file against the publisher's hash
• Check file integrity — ensure a file wasn't corrupted during transfer
• Deduplicate — find identical files by comparing SHA-256 hashes

Files are hashed entirely in your browser using the Web Crypto API. Even multi-gigabyte files never leave your machine.

Generate Hashes in Code

JavaScript (Web Crypto)

async function sha256(text) {
  const data = new TextEncoder().encode(text);
  const hash = await crypto.subtle.digest('SHA-256', data);
  return Array.from(new Uint8Array(hash))
    .map(b => b.toString(16).padStart(2, '0')).join('');
}

Python

import hashlib
hashlib.sha256(b'hello world').hexdigest()
hashlib.md5(b'hello world').hexdigest()

Bash

echo -n "hello world" | sha256sum
echo -n "hello world" | md5sum
sha256sum myfile.iso

Hash Comparison Tool

Our generator includes a built-in hash comparison tool. Paste two hashes side-by-side and instantly see if they match — with character-by-character highlighting for mismatches. Perfect for verifying file downloads.

Security Notes

• MD5 and SHA-1 are broken for security — don't use them for passwords, signatures, or any security-critical application
• For passwords, use bcrypt, scrypt, or Argon2 — plain SHA-256 is too fast for password hashing (makes brute-force easy)
• SHA-256 is fine for checksums, HMACs, and data integrity
• Our tool runs client-side — we never see your data

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