Probability Calculator

Find the chance of an event happening. Find the chance of an event and of it happening at least once in several tries.

How to use Probability Calculator

  1. Enter your values. Phones show the number keypad for number fields.
  2. Press Calculate.
  3. Read the result below.

Features

  • Free to use with no signup
  • Works on phones, tablets and computers
  • Runs in your browser, so your data stays on your device
  • Nothing to install

Frequently asked questions

How is 'at least once' calculated?

1 - (1 - p)^n, where p is the chance in one try and n is the number of independent tries.

Is my data safe?

This tool runs inside your browser. Your text and files are not uploaded to our server.

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