Convert success/failure weights into event odds and probability, then compare all-success and at-least-one independent repetition events.
How to use this tool
- Choose the event or model and review the assumptions below.
- Enter the labeled inputs. Probability inputs are percentages from 0 to 100, not decimal fractions.
- Select Calculate and read the labeled outputs.
- Change an input and calculate again; Reset restores the example inputs.
Calculation method
Probability from odds a:b is a/(a+b). Probability of all n independent successes is pⁿ; at least one is 1−(1−p)ⁿ.
Assumptions and limits
Weights describe relative chances, not the count of listed outcomes unless equally likely. Repetition outputs assume independent trials with constant probability. Quoted market margins belong to the existing Implied Probability Calculator.
Worked example
Success weight 1 and failure weight 4 imply probability 20%. Across three independent trials, all-success probability is 0.8% and at-least-one probability is 48.8%.
Worked reading and practical questions
- Odds in Favor and Odds Against: Put the Weights in the Right Order
- Repeated Chances: All Successes vs At Least One
Browse Statistics calculators or explore other tools on the GreenCalc homepage.
Frequently asked questions
What does this calculator assume?
Weights describe relative chances, not the count of listed outcomes unless equally likely. Repetition outputs assume independent trials with constant probability. Quoted market margins belong to the existing Implied Probability Calculator.
How do I enter and update the inputs?
Use the labeled fields, then select Calculate. Percent fields use 0 to 100. After editing, calculate again; Reset restores the example inputs.