A hash is a fixed-length fingerprint calculated from input data.

HMAC combines a cryptographic hash with a secret key to authenticate data.

Can hashes be reversed?

Cryptographic hashes are designed to be one-way and cannot be directly decoded.

Developer ToolDeveloper Tool

Hash & HMAC Generator

Generate MD5 and SHA fingerprints or keyed HMAC values for text, API testing, and integrity checks.

5 common algorithmsOptional HMACInstant output

Use HMACUppercase

Hashes Ready

Input text

Hash values generated successfully.

Generated Values

Click any result to copy it.

MD5

caa6b37649971c6ff52d7a1fd7d40f28

SHA-1

a2eabb1e3d0f4d79da096d99a3d5bf1caa0e808e

SHA-256

0e8608c1ec79a600c4297c5a788e7b4ae6b19c2d6486bc90ee54bf194b43cfe5

SHA-384

df7a22ce560f81ccffbd77d8dcd00c0478800d43f9fd7237afd00eff8fceda688fe42a842dab41a67146151f5d970355

SHA-512

b04ba3c946b52eba10c7929f93b35087285ceaf14d53316f19e58646a7fe88d087f5b2e19f8eadcdb4a180ca5d80531831d26234d8c028c4485bf1b089bee77b

Bcrypt Password Hasher

Password Safe

Generate salted password hashes and verify passwords against them.

Password

Cost factor

Use test data here. Production passwords should be hashed directly inside your application.

Bcrypt hash

Enter a password to generate a secure bcrypt hash.

How to Use

1Enter TextPaste the value you want to hash.
2Choose HMACOptionally provide a secret key.
3ReviewCompare five generated algorithms.
4CopyCopy one value or the full set.

Technical Specs

Algorithms: MD5 + SHA + Bcrypt
HMAC: All digest algorithms
Bcrypt Cost: 10–14
Maximum Size: 1 MB

Integrity and authentication

Hashing is not encryption

A hash is a one-way fingerprint and cannot be decoded like Base64. Use SHA-256 or stronger for integrity checks. MD5 and SHA-1 remain useful for legacy compatibility and non-security checksums, but should not protect passwords or security-sensitive data.

Frequently Asked Questions

Can a hash be reversed?+

No direct decoding operation exists. Weak inputs can still be guessed and compared against their hashes.

Why does bcrypt change every time?+

Bcrypt creates a fresh random salt for every hash. Different hashes can all correctly verify the same password.

Which algorithm should I use?+

Use SHA-256 for general integrity checks and bcrypt or Argon2id for passwords.

What is HMAC?+

HMAC combines a hash algorithm with a secret key to verify message authenticity and integrity.

Are MD5 and SHA-1 secure?+

Not for collision-resistant security. They are included for legacy interoperability and checksums.

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