Free · Expected values

Probability-Weighted Loss Comparison

Compare the expected monetary loss of two events from each event’s probability and loss amount.

Calculator inputs

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Enter the known values in the units shown. Results update as you type.
Where results are editable, change one to solve backwards. Lock a value to hold it fixed.
Use the worked example to check the method. Reset restores the starting fields.

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A 10% chance of losing 1,000 gives expected loss of 100. A 2% chance of losing 5,000 also gives 100, despite very different possible outcomes.

Expected loss = event probability × loss if the event occurs

Enter these known values and leave the other values blank.

Each option has the entered loss when its event occurs and zero loss otherwise. Other outcomes or costs require a fuller distribution.
Probabilities are from 0% to 100% and monetary losses are nonnegative. Compare amounts in the same currency and scale.
Expected loss is a probability-weighted average, not a forecast of the loss in one trial or a complete measure of risk.
Currency selectors use fixed captured exchange rates and do not fetch current market rates.

No. Rare large losses and frequent small losses can have the same expectation but different consequences.

Yes. Enter expected loss and a positive loss amount. The resulting probability must remain between zero and one.

Compare signed differences of expected losses so small differences are not erased by approximate equality.