Expected Value Calculator
Find the expected value from outcomes and probabilities.
The average outcome
Expected value is the average result you would see over many repetitions: each possible outcome weighted by how likely it is. It is the foundation of decisions under uncertainty, from bets to business.
With outcomes of 100, 50, and -20 at probabilities of 0.25, 0.5, and 0.25, the expected value is 45. A positive expected value means the bet or decision pays off on average.
Insightful and private
The calculation runs in your browser, so your data is never uploaded.
Frequently Asked Questions
What is expected value?
The long-run average outcome — each value multiplied by its probability, all summed.
How do I enter data?
One outcome per line as a value and its probability, like 100 0.25.
Should probabilities sum to 1?
Ideally yes. The tool shows the probability total so you can check.
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