Hash Collision Probability Calculator
Using the birthday paradox approximation, estimate the chance that at least two hashes collide for a given number of hashes and hash size.
CalcSimpler Examples
- 100,000 hashes, 32-bit hash ⇒ 68.8%
- 1,000,000 hashes, 64-bit hash ⇒ 0.0000027%
FAQ
Why use the birthday paradox?
It approximates collision probability for large sample spaces.
Does increasing hash size reduce collisions?
Yes, more bits drastically lower collision risk.
Is the formula exact?
It's an approximation assuming uniform hash distribution.
Additional Information
- Probability grows roughly with the square of the number of hashes.
- Cryptographic algorithms often use 256-bit hashes to minimize collisions.
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