Probability Fraction Calculator

The probability of an event is a measure of how likely that event is to occur relative to all possible outcomes. It is calculated as the ratio of favorable outcomes to total possible outcomes, and always falls between 0 (impossible) and 1 (certain).

Yes — a fraction is one of the most natural ways to express probability. The numerator represents the number of favorable outcomes and the denominator represents the total number of possible outcomes. For example, rolling a 3 on a standard die has a probability of 1/6.

Divide the number of favorable outcomes by the total number of possible outcomes, then simplify the fraction by dividing both numbers by their greatest common divisor (GCD). For instance, 4 favorable outcomes out of 8 total simplifies to 1/2.

A fair coin has 2 possible outcomes (heads or tails). The probability of getting heads is 1/2, and the same applies to tails. This means each outcome has an equal 50% chance.

For independent events, multiply their individual probabilities together. For example, if Event 1 has probability 1/2 and Event 2 has probability 1/3, the combined probability of both occurring is 1/2 × 1/3 = 1/6. This calculator handles up to 5 events simultaneously.

Simplifying means reducing the fraction to its lowest terms by dividing both the numerator and denominator by their greatest common divisor. For example, 6/8 simplifies to 3/4. The value of the probability doesn't change — only its representation is made simpler.

Yes. This calculator assumes all events are independent of each other, meaning the outcome of one event does not affect the others. For dependent events (e.g. drawing cards without replacement), a different approach using conditional probability is required.

They are all equivalent representations of the same value. A fraction like 1/4 equals 0.25 as a decimal and 25% as a percentage. Fractions are often preferred in theoretical probability because they show the exact ratio without rounding errors.