The Combination & Permutation Calculator is a free, accurate online tool designed to help you solve everyday math problems quickly in seconds. Just enter total items (n), chosen (r) and instantly see permutations (npr), combinations (ncr). Math problems can quickly become tedious or error-prone when done by hand, especially when you need to repeat the same calculation across different inputs. This tool standardizes the process and gives you a reproducible answer every time, with full step-by-step working you can verify. Under the hood, the tool applies the standard formula: C(n, r) = n! / (r!(n-r)!) for combinations, P(n, r) = n! / (n-r)! for permutations. You can see exactly how the result is derived, which is especially useful for students, professionals, and anyone who wants to learn rather than just get an answer. CalcPlanet builds every calculator to be fast, mobile-friendly, and free, with no signup required. We test results against worked examples and reference implementations so you can rely on what you see. Enter your values above to get an instant, accurate combination & permutation calculator result, then explore the FAQs and examples below for deeper context. You can use this calculator for homework, study sessions, exam prep, or quick sanity checks during real-world projects. Each result is shown with the underlying values so you can see exactly how the answer was derived. If you are learning the topic, try working a problem by hand first and then verify your answer here. Bookmarking this page makes it easy to revisit when you need a quick refresher on the formula and how it is applied in practice.
The Combination & Permutation Calculator is a free, accurate online tool designed to help you solve everyday math problems quickly in seconds. Just enter total items (n), chosen (r) and instantly see permutations (npr), combinations (ncr). Math problems can quickly become tedious or error-prone when done by hand, especially when you need to repeat the same calculation across different inputs. This tool standardizes the process and gives you a reproducible answer every time, with full step-by-step working you can verify. Under the hood, the tool applies the standard formula: C(n, r) = n! / (r!(n-r)!) for combinations, P(n, r) = n! / (n-r)! for permutations. You can see exactly how the result is derived, which is especially useful for students, professionals, and anyone who wants to learn rather than just get an answer. CalcPlanet builds every calculator to be fast, mobile-friendly, and free, with no signup required. We test results against worked examples and reference implementations so you can rely on what you see. Enter your values above to get an instant, accurate combination & permutation calculator result, then explore the FAQs and examples below for deeper context. You can use this calculator for homework, study sessions, exam prep, or quick sanity checks during real-world projects. Each result is shown with the underlying values so you can see exactly how the answer was derived. If you are learning the topic, try working a problem by hand first and then verify your answer here. Bookmarking this page makes it easy to revisit when you need a quick refresher on the formula and how it is applied in practice.
The Combination & Permutation Calculator on CalcPlanet is engineered for accuracy, speed and zero friction. Enter your numbers, see results instantly, and explore the full formula and worked example below — no signup, no paywall, no tracking of your inputs.
C(n, r) = n! / (r!(n-r)!) for combinations, P(n, r) = n! / (n-r)! for permutations
((function(){ var n_val = parseFloat(n); var r_val = parseFloat(r); function factorial(k) { if (k < 0) return NaN; if (k === 0 || k === 1) return 1; let res = 1; for (let i = 2; i <= k; i++) res *= i; return res; } if (isNaN(n_val) || isNaN(r_val) || n_val < 0 || r_val < 0 || r_val > n_val || !Number.isInteger(n_val) || !Number.isInteger(r_val)) return null; var combinations = factorial(n_val) / (factorial(r_val) * factorial(n_val - r_val)); return combinations; })()).toString() + ' (Combinations), ' + ((function(){ var n_val = parseFloat(n); var r_val = parseFloat(r); function factorial(k) { if (k < 0) return NaN; if (k === 0 || k === 1) return 1; let res = 1; for (let i = 2; i <= k; i++) res *= i; return res; } if (isNaN(n_val) || isNaN(r_val) || n_val < 0 || r_val < 0 || r_val > n_val || !Number.isInteger(n_val) || !Number.isInteger(r_val)) return null; var permutations = factorial(n_val) / factorial(n_val - r_val); return permutations; })()).toString() + ' (Permutations)'
n represents the total number of items available, and r represents the number of items to choose from the set.
Yes. Every calculator on CalcPlanet is 100% free, requires no signup, and runs entirely in your browser. There are no usage limits and no paywall.
The calculator applies the standard formula (C(n, r) = n! / (r!(n-r)!) for combinations, P(n, r) = n! / (n-r)! for permutations) and is tested against worked examples. Results are accurate to the precision of the inputs you provide.
Yes. CalcPlanet is fully mobile-optimized. The interface, inputs, and results all adapt to phones and tablets, and you can save the page as a home-screen shortcut for one-tap access.
No. All calculations run locally in your browser. Your inputs never leave your device unless you explicitly choose to share or save a result.
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