Probability Calculator
Calculate single-event probability and the complement.
About this calculator
The Probability Calculator on NumberCals is a free, mobile-friendly tool for anyone needing to calculate single-event probability and the complement. Enter your values in the form below and the result is computed instantly — no sign-up, no installation, no waiting.
Formula used
P(A) = favorable / total
What you'll need
- Favorable Outcomes (e.g. 1)
- Total Possible Outcomes (e.g. 6)
What you'll get
- Probability
- Probability (%)
- Probability NOT (%)
- Odds (favorable:unfavorable)
Formula
P(A) = favorable / total
Result
Frequently Asked Questions
Probability vs odds? +
Probability = favorable/total. Odds = favorable:unfavorable. P=0.25 → odds 1:3.
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