Statistics & Probability

Instant, private, and free

Birthday Paradox Calculator.

Calculate birthday paradox from explicit inputs using the documented formula.

On-device calculationNo signup
01

Set your values

Results update as you type.

collisionProbability: 0.507297

collisionProbability

0.000000
noCollisionProbability: 0.492703

noCollisionProbability

0.000000

Results update automatically as you type.

FAQs

What does this calculator assume?

Calculate birthday paradox from explicit inputs using the documented formula. No unstated input convention is inferred.