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Bcrypt Generator & Verifier

Generate secure bcrypt password hashes with a chosen cost factor, and verify a password against an existing hash. Free, using native bcrypt.

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🔒 How bcrypt works

  • bcrypt is a slow, salted password-hashing algorithm designed to resist brute-force attacks.
  • Every hash embeds a unique random salt, so the same password produces a different hash each time.
  • Hashing is one-way — you verify a password by re-hashing and comparing, never by decrypting.

Free Bcrypt Generator & Verifier

Generate secure bcrypt password hashes and verify a password against an existing hash. Choose the cost factor, copy the hash, and confirm matches — powered by the same battle-tested bcrypt algorithm used in production frameworks. Free, with no account required.

What is bcrypt?

Bcrypt is a password-hashing algorithm designed specifically for storing passwords securely. Unlike fast, general-purpose hashes such as MD5 or SHA-256, bcrypt is deliberately slow and includes a built-in salt, which makes large-scale brute-force and rainbow-table attacks impractical. It has been trusted for over two decades and remains a recommended default for password storage in modern web frameworks.

How to use this tool

There are two modes:

  • Generate — enter a password, pick a cost factor, and get a bcrypt hash to store in your database.
  • Verify — paste a password and an existing bcrypt hash to check whether they match.
  • Copy the generated hash with one click.
  • Adjust the cost factor to balance security against server speed.

What is the cost factor?

The cost factor (also called work factor or rounds) controls how much computation each hash takes. bcrypt runs 2 to the power of the cost — so a cost of 10 means 2^10 = 1024 rounds, and each extra point doubles the work. Higher costs make hashes slower to compute, which slows attackers down, but also adds load to your server on every login. A cost of 10 to 12 is a common, sensible choice for most web applications.

Why every bcrypt hash is different

bcrypt automatically generates a random salt for each hash and stores it inside the output string. That is why hashing the same password twice produces two completely different hashes — and why you should never see duplicate hashes even for users who chose the same password. When verifying, bcrypt reads the salt and cost from the stored hash, re-hashes the supplied password the same way, and compares the results.

How to store and check passwords correctly

Never store passwords in plain text or with a fast hash. Instead, hash the password with bcrypt when a user registers, store only the hash, and at login re-hash the entered password and compare — which is exactly what the Verify mode does. Because bcrypt is one-way, there is no way to decrypt a hash back to the original password; you can only test whether a candidate password matches.

Pro tip

Use bcrypt (or Argon2) for passwords, and reserve SHA-256 for checksums and integrity, not password storage. Increase your cost factor over the years as hardware gets faster, and re-hash a user's password at login when you raise it. For non-password hashing, see our SHA-256 Hash Generator.

FAQ

Is this bcrypt tool free?
Yes. Generating and verifying bcrypt hashes is completely free and requires no account or sign-up.
Can a bcrypt hash be reversed or decrypted?
No. bcrypt is a one-way hashing algorithm. You cannot recover the original password from a hash — you can only verify whether a given password matches by re-hashing and comparing.
Why does the same password produce a different hash each time?
bcrypt generates a unique random salt for every hash and embeds it in the output. This means identical passwords produce different hashes, which protects against rainbow-table attacks.
What cost factor should I use?
A cost of 10 to 12 is a sensible default for most web applications. Higher values are more secure but slower. Choose the highest cost your server can handle without noticeable login delay.
How do I verify a password against a bcrypt hash?
Use the Verify tab: paste the plain password and the stored bcrypt hash. The tool re-hashes the password with the salt from the stored hash and tells you whether they match.
Is bcrypt better than MD5 or SHA-256 for passwords?
Yes, for passwords. MD5 and SHA-256 are fast, which helps attackers. bcrypt is intentionally slow and salted, making it far more resistant to brute-force attacks. Use bcrypt or Argon2 for passwords.
What does a bcrypt hash look like?
It starts with a prefix like $2y$, $2a$, or $2b$, followed by the cost and a 22-character salt, then the hash — for example $2y$10$... The whole string is 60 characters long.

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Pro tip: pair this tool with Upside Down Text Generator and Text Similarity Checker for a faster SEO workflow.