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Calcimator

Probability Calculator

Calculate probability of single events, combined events (AND/OR), permutations, and combinations.

Inputs

%
%

Results

Result

50

Complement (NOT)50%
Odds1 in 2
At Least Once in N Trials99.9%

Result

50

How to Use This Calculator
  1. Start by filling in the input fields below. Results update instantly as you type, so you can experiment with different values to see how they affect the outcome.
  2. Calculation Type — Calculation mode to use. Choose from: Single Event, A AND B (both occur), A OR B (either occurs), Permutations (nPr), Combinations (nCr). default: 0.
  3. Probability A — enter a percentage value. Accepts values from 0 % to 100 % (default: 50 %).
  4. Probability B — enter a percentage value. Accepts values from 0 % to 100 % (default: 30 %).
  5. Total Items (n) — enter a numeric value. Accepts values from 0 to 20 (default: 10).
  6. Chosen Items (r) — enter a numeric value. Accepts values from 0 to 20 (default: 3).
  7. Number of Trials — enter a numeric value. Accepts values from 1 to 1,000 (default: 10).
  8. Once all inputs are set, review your results in the Results panel. Here's what each output means:
  9. Result — shown as a numeric value. This is the primary result of this calculator.
  10. Complement (NOT) — shown as a numeric value.
  11. Odds — your calculated result.
  12. At Least Once in N Trials — shown as a numeric value.
  13. View the Probability Distribution below for a visual breakdown of how the numbers relate to each other.
  14. Explore the related calculators below if you need deeper analysis or want to approach this topic from a different angle.
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