Complement Probability
An event and its complement cover all outcomes without overlap. Their probabilities therefore sum to one.
Complement Probability
Probability · 1 input
How to use this calculator
- Enter event probability in 0–1.
- Select Calculate and keep the output unit with the answer.
Before you use the answer
Choose the reference quantity before interpreting the number. A ratio, a percentage and a percentage-point difference may use the same observations while answering different questions. For recorded data, keep the original values beside the summary so an unexpected result can be traced back to its inputs.
The complement means the event does not occur, not a different event that can overlap it.
Does it save my inputs?
No calculation history is stored by this website. The calculator works locally in your browser. See the privacy policy for hosting and contact details.
Why might a result be approximate?
Measurement uncertainty, ideal-model assumptions and floating-point rounding can all matter. Displaying more digits does not improve the original measurement.
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