Statistics & probability

Simple probability

Calculate probability from favorable and total outcomes.

LocalFree
Study & learning use only
Use the result as a learning aid and verify important calculations against your course material or instructor.
This tool runs on your device in the browser.
Instructions and limitations
TOOL GUIDE

What this tool is for

Simple probability — Calculate probability from favorable and total outcomes.

Useful for practice, understanding the method, and checking homework steps where outside tools are allowed.

Common uses
  • Practice a formula or method
  • Check your working
  • Review before a lesson or exam
Study and learning use only

Use the result for practice and understanding, not as a guaranteed answer. Verify important calculations and follow your school, university, and academic-integrity rules.

EXPLANATION & EXAMPLE

Understand the result—not just the number

Core ideaP=favorable/total

Probability is the fraction of equally likely outcomes that satisfy the event.

Quick exampleUse the starting values, then change one input to see its effect.

After calculating, the tool shows the values used and the working so you can check it.

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