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Math & AlgebraGenerated accuracy model review: 2026-05-06

Probability Calculator accuracy and testing

This page documents how Calwarden builds trust for this calculator: source notes, regression-style default tests, limitations, assumptions, unit handling, rounding, and visible change history.

Formula source

  • **Probability (P)** = Desired Outcomes / Total Outcomes. For two independent events (A and B occurring): **P(A and B) = P(A) × P(B)**.

Test cases

Default input regression check

Generated from the checked-in default inputs and calculate function.

Inputs

  • Mode: Single Event
  • Event A: Desired Outcomes: 1
  • Event A: Total Outcomes: 6
  • Event B: Desired Outcomes: 1
  • Event B: Total Outcomes: 2

Expected outputs

  • Probability: 16.67%
  • 1 in X Chance: 1 in 6.0

Known limitations

  • This page documents the checked-in calculator logic and does not certify results for every real-world edge case.
  • Use the result as a planning estimate unless the calculator page states a stricter purpose.

Assumptions

  • Desired outcomes cannot exceed total outcomes for a valid probability.
  • The two-event mode assumes independence between Event A and Event B.
  • Probabilities stay between 0% and 100%, so invalid counts are rejected instead of producing impossible percentages.

Unit handling

  • Mode accepts one of the configured options.
  • Event A: Desired Outcomes accepts numeric values.
  • Event A: Total Outcomes accepts numeric values.
  • Event B: Desired Outcomes accepts numeric values.
  • Event B: Total Outcomes accepts numeric values.
  • Probability is displayed as a percentage.

Rounding rules

  • Number displays use up to 2 decimal places in the calculator UI.
  • Percent outputs are displayed with two decimal places.

Version history

1.0.0 - 2026-05-06

Generated accuracy and testing page from the current probability-calculator calculator definition.

Change log

2026-05-06

Published default regression test documentation and metadata fallbacks for Probability Calculator.

Calculator transparency

Accuracy pages are generated from checked-in calculator definitions and can be upgraded with curated review metadata over time.

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