What this calculator does
This permutation calculator is built for the moment you need a defensible number — quoting a client, comparing options, or checking someone else's math — not a generic estimate.
Permutations count ordered arrangements.
How to use the Permutation Calculator
- Enter your values in the fields on the left.
- Results update automatically.
- Use action buttons to copy, share or print.
The formula
P(n,r) = n! / (n−r)!
Worked example
P(10,3) = 720.
Common mistakes
- Confusing with combinations
- r > n
- Negative values
When to use it
Use for arranging, ranking, sequences.
Pro tips for the Permutation Calculator
- The chart updates live — drag values up and down to build intuition for how the formula behaves.
- Change one input at a time to see which lever actually moves the answer the most.
- Round-trip check: reverse the inputs to confirm the formula matches what you'd compute by hand.
Frequently asked questions
›Permutations vs combinations?
Permutations order; combinations don't.
›Repeated elements?
Divide by factorials of repeats.
›P(n,n)?
n! (all arrangements).
›0!?
1 by definition.
›Fast compute?
Grows factorially.
›How accurate is this permutation calculator?
The formulas match the standard textbook definition shown above. Rounding is applied only for display; underlying computation uses full floating-point precision. For regulated math & education decisions, always confirm with a qualified professional.
›Can I use this on mobile?
Yes — the permutation calculator is fully responsive, and results, charts, and the share button all work on phones and tablets.
Embed this calculator
Drop the Permutation Calculator into your own site or blog post. Free to use — a small “Powered by CalcPilot” link is appreciated.
<iframe src="https://calcpilot.tools/calculators/permutation-calculator?embed=1" width="100%" height="720" style="border:1px solid #e5e7eb;border-radius:12px;max-width:720px;" loading="lazy" title="Permutation Calculator — CalcPilot"></iframe>Related calculators
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