Probability Calculator
Probability (%) = Favorable outcomes ÷ Total outcomes × 1001 favorable face ÷ 6 equally likely faces × 100 = 16.6667%
Free online tool
Probability Calculator
Count favorable outcomes and all possible outcomes in a finite set where each outcome is equally likely. The result is a percentage, such as 1 out of 6 = 16.6667%.
Instant calculation
Probability Calculator
Enter favorable outcomes and total outcomes to find the probability.
Your result
Calculation
Your numbers stay in this browser. Nothing is uploaded or saved.
Three clear steps
How to use this calculator
- 01
Enter favorable outcomes
Type the number of ways the event can occur.
- 02
Enter total outcomes
Type the total number of possible outcomes.
- 03
See probability
Calculate to see the probability as a percentage. Divide the displayed percentage by 100 if you need the 0–1 decimal form.
The formula
How this calculation works
Divide the number of favorable outcomes by the total number of equally likely outcomes, then multiply by 100. The displayed result ranges from 0% to 100%; total outcomes must be positive and favorable outcomes cannot exceed the total.
Check the method
Worked examples
Each example follows the same formula used by the calculator.
Rolling a 6 on a fair six-sided die?
1 favorable face ÷ 6 equally likely faces × 100 = 16.6667%About 16.67%Common questions
Questions about this calculation
What is the Probability Calculator?
The Probability Calculator helps you calculate the probability of an event from favorable and total outcomes. Enter your values and select Calculate to get an instant result.
How is the result calculated?
Classical probability formula. Result is between 0 (impossible) and 1 (certain).
Can you show an example?
Example: Rolling a 6 on a fair die? — ≈ 0.1667 (16.67%).
Is my data saved when I use the Probability Calculator?
No. All calculations run locally in your browser. Your inputs and results are never uploaded, stored or shared with anyone.
Is the Probability Calculator free to use?
Yes. The Probability Calculator is completely free. No account, sign-up or payment is required. It works on mobile, tablet and desktop.
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