Probability Calculator

Probability as a decimal, percentage, and odds.

Quick answer: Calculate statistical probabilities online. Convert outcomes into precise decimals, percentages, and odds securely in your browser.

Probability0.1667
As percentage16.67%
As odds1 : 5
Complement (not happening)0.8333

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Convert favorable and total outcomes into a probability, expressed as a decimal, a percentage, and odds, plus the chance of the event not happening.

How it works

  1. Enter the number of favorable outcomes (e.g., 1 for a specific die roll).
  2. Enter the total possible outcomes (e.g., 6).
  3. Review the calculated probability and true odds ratio.

Frequently asked questions

Probability vs odds?

Probability is favorable / total (1/6 for a die roll); odds compare favorable to unfavorable (1:5).

What is the complement?

The probability an event does not happen: 1 minus the event probability. They always sum to 1.

How do I combine probabilities?

For independent events, multiply for "and", add (minus overlap) for "or". This tool covers single events.

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