Probability Calculator

Calculate probability and odds from favorable and total outcomes.

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What This Calculator Does

Calculate probability and odds from favorable and total outcomes.

It combines Favorable Outcomes, Total Outcomes to estimate Probability, Odds For, Odds Against.

Formula & Method

Probability is

P=\frac{Favorable}{Total}

and percent

P\%=100P

. Odds for are

\frac{Favorable}{Unfavorable}

and odds against are

\frac{Unfavorable}{Favorable}

Notation used in the formulas: $R$ = Probability; $x_{1}$ = Favorable Outcomes; $x_{2}$ = Total Outcomes.

Method summary: inputs are normalized to consistent units, core equations are evaluated, then secondary values are derived and rounded for display.

Use this calculator for quick scenario analysis. Start with baseline values, change one driver at a time, and compare how sensitive the results are to each input shown above.

Reference Book

Games, Gambling, and Probability

An Introduction to Mathematics

David G. Taylor · Chapman and Hall/CRC

A natural reference for odds, card draws, poker-style counting, gambling expectations, and game probability.

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Inputs Used

Favorable Outcomes: Used directly in the calculation.
Total Outcomes: Used directly in the calculation.

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