Bayes' theorem calculates posterior probabilities based on prior and likelihood.
P(A|B) = P(B|A) × P(A) / P(B)
Reach for this calculator when you need a result you can act on confidently. The formula is straightforward, but manual computation introduces rounding errors that this tool eliminates entirely.
Many errors with this type of calculation stem from unit inconsistency: mixing metric and imperial, or mixing annual and monthly rates. Ensure all inputs use the same unit system before running the calculation.
A business owner spots that revenue grew from £180,000 last year to £213,400 this year. The calculator confirms the increase is 18.6% — a figure needed for the annual report and for comparing against the industry growth rate cited in the sector report.
A formula to update probability estimates based on new information.
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