Statistics

Hypergeometric Distribution Calculator

Draws without replacement — cards, lotteries, quality samples.

Enter your values

ⓘ Live results

Results
P(exactly k)
27.428%
P(at most k)
90.7233%
P(at least k)
36.7047%
Expected successes
1.25
Standard deviation
0.93

Quick answer

The hypergeometric distribution models sampling without replacement: P(X = k) = C(K,k)·C(N−K,n−k) ÷ C(N,n).

P(X = k) = C(K,k)·C(N−K,n−k) ÷ C(N,n)

How to use the Hypergeometric Distribution Calculator

  1. 1Enter the total population and how many of them count as successes.
  2. 2Enter how many items you draw.
  3. 3Enter the number of successes you want in the draw.

Worked example

Using the values the calculator loads with:

Inputs

  • Population size N52
  • Successes in the population K13
  • Sample drawn n5
  • Successes wanted k2

Results

  • P(exactly k)27.428%
  • P(at most k)90.7233%
  • P(at least k)36.7047%
  • Expected successes1.25
  • Standard deviation0.93

Frequently asked questions

When should I use binomial instead?

When you replace each item, or when the sample is under about 5% of the population — then the two answers barely differ.

Can it handle lottery odds?

Yes. Set N to the ball count, K to the numbers on your ticket, n to the balls drawn and k to the matches.

About this calculator

Results are estimates for general information. For medical, legal, structural or financial decisions, confirm with a qualified professional.