SESKStuff Everyone Should Know
SESK: Stuff Everyone Should Know · sesk.info/tech-password-salt

Why is a unique salt added before hashing a password?

A salt makes identical passwords produce different stored hashes.

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  1. It shortens every password
  2. It prevents all phishing
  3. It separates otherwise identical hashes ✔

Why: The verifier combines a random salt with each password before hashing. Attackers cannot reuse one precomputed hash table efficiently across many accounts, even when users chose the same password.

Huh, didn't know that: NIST requires each salt to be at least 32 bits long and stored along with the hash.

The dad joke
The hash asked for salt because plain passwords were tasteless.
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References

Answer: It separates otherwise identical hashes. The verifier combines a random salt with each password before hashing. Attackers cannot reuse one precomputed hash table efficiently across many accounts, even when users chose the same password.

  1. NIST SP 800-63B pages.nist.gov/800-63-4/sp800-63b.html
    to prevent multiple subscriber accounts from having the same hashed password
    Checked 2026-10-10.

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