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Both calculators run independently — change the inputs on either side to compare results.

Bayes' Theorem Calculator

Compute the posterior probability P(A|B) from a prior belief, a likelihood, and a false-positive rate. Use it for medical testing, spam filtering, or any scenario where you update beliefs with new evidence.

Prior Probability P(A)

Likelihood P(B|A)

Likelihood P(B|¬A)

Fill in the required fields to see your result.

Probability

Expected Value Calculator

Compute the expected value (mean) of a discrete probability distribution by entering up to three outcomes and their probabilities. Ideal for decision analysis, gambling odds, and statistics coursework.

Outcome 1 Value

Outcome 1 Probability

Outcome 2 Value

Outcome 2 Probability

Outcome 3 Value

Outcome 3 Probability

Fill in the required fields to see your result.

Key differences

	Bayes' Theorem Calculator	Expected Value Calculator
Category	Probability	Probability
Inputs required	3	6
Result	Posterior Probability P(A\|B)	Expected Value
What it does	Compute the posterior probability P(A\|B) from a prior belief, a likelihood, and a false-positive rate. Use it for medical testing, spam filtering, or any scenario where you update beliefs with new evidence.	Compute the expected value (mean) of a discrete probability distribution by entering up to three outcomes and their probabilities. Ideal for decision analysis, gambling odds, and statistics coursework.