Why can one hash have several possible algorithms?

Several algorithms produce the same output length. A 64-character hex string could be SHA-256, SHA3-256 or BLAKE2s-256. Length alone can only narrow the list.

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Hash identifier

Paste a hash and get the likely algorithms. Length and prefix are clues, not proof; the page says which part is which.

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Hash

Paste a hash to narrow down what it might be.

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Read the hashing lessonSecurity+ path: cryptography and storage Try a crypto labCompare hashing and encryption

Questions

No. It identifies likely algorithms from length and prefix. Reversing a password hash means guessing candidate passwords, which is a different and slower job. This page does not run a cracker and does not send the hash anywhere.

Know the algorithm before you talk about the control

Security+ questions ask why a password store uses bcrypt or Argon2 instead of SHA-256. SecLern lessons explain the why, then a lab makes you compare them.

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