Is Probability Calculator completely free?

Yes, completely free with unlimited calculations. No registration, login, or payment required. Access all features instantly.

What types of probability can I calculate?

Calculate simple probability, combinations (nCr), permutations (nPr), conditional probability, and binomial probability. Each calculation type includes step-by-step formulas.

Does this work on mobile devices?

Yes, fully responsive. Works on iPhone, Android, iPad, tablets, and desktop computers with any modern browser.

What are the input limits?

Enter numbers from 0 to 1,000,000. The calculator handles large numbers efficiently without requiring scientific notation entry.

Yes, all calculations happen in your browser. No data is saved, sent to servers, or stored. Your privacy is completely protected.

What's the difference between combinations and permutations?

Combinations (nCr) count selections where order doesn't matter (choosing 3 people from 10). Permutations (nPr) count arrangements where order matters (ranking 3 people from 10). This calculator computes both instantly.

Can I use this for homework or exams?

Yes, use it to verify answers and understand probability concepts. The detailed formula breakdown helps you learn how each calculation works, making it educational for students.

What output formats are available?

Results display as decimals (0.25), percentages (25%), fractions (1/4), odds ratios (1:3), and probability explanations in plain English.

fast

Probability Calculator — fast

Calculate basic probability and combinations.

Favorable outcomes

Total outcomes

Fraction

1/2

Decimal

0.500000

Percentage

50.0000%

How to use Probability Calculator

Select Your Calculation Type

Click the dropdown menu labeled 'Calculation Type' at the top of the calculator. Choose between 'Simple Probability', 'Combinations (nCr)', 'Permutations (nPr)', or 'Conditional Probability' based on your needs.

Enter Your Numbers in the Input Fields

Input your values into the numeric fields that appear. For Simple Probability, enter 'Favorable Outcomes' and 'Total Outcomes'. For Combinations/Permutations, enter 'n' (total items) and 'r' (items to choose). Fields show examples in light gray placeholder text.

Click Calculate Button

Press the blue 'Calculate' button below the input fields. Results display instantly in the 'Results' panel showing the probability as a decimal, percentage, fraction, and odds ratio.

View Detailed Breakdown

Scroll to the 'Calculation Details' section to see the formula used, step-by-step computation, and explanation. Click 'Copy Result' to copy the answer to your clipboard or 'Reset' to clear fields.

Frequently Asked Questions

Related Tools

🔢

Statistics Calculator

Calculate mean, median, mode, and standard deviation.

🔢

Percentage Calculator

Calculate percentages easily: find X% of Y, percentage change, percentage difference, and more.

🔢

Random Number Generator

Generate random numbers within a custom range.