Calculate P(n,r) and C(n,r) with step-by-step formulas.
Loading Permutation & Combination…
Permutation-Combination Calculator computes nPr (permutations) and nCr (combinations) from n total items and r chosen, the core counting tools of probability and statistics.
The whole distinction comes down to one question: does order matter? Permutations count arrangements where it does (a race podium, a password, a sequence), while combinations count selections where it doesn't (a committee, a hand of cards, a group). Asking 'if I rearrange the chosen items, is it a different outcome?' resolves almost every permutation-vs-combination problem.
Mathematically, nPr = n! ÷ (n−r)! and nCr = n! ÷ (r!(n−r)!), the only difference being that combinations divide by an extra r! to strip out the duplicate orderings permutations count separately. That's why nCr is always less than or equal to nPr for the same inputs.
Because these use factorials, the numbers explode quickly (10! exceeds 3.6 million), which is exactly why they're calculated rather than counted by hand. The calculation runs in your browser with nothing uploaded. Pair it with the Logarithm and other ToolsMonk student and STEM tools for your maths coursework.
| Price | Free, no signup, no paywall, no watermark |
|---|---|
| Works on | Any modern browser: desktop, tablet, and mobile |
| Processing | In your browser, files never leave your device |
| Account required | None |
| Category | Student Tools |
Enter n (total items) and r (number chosen)
The tool calculates both nPr (permutations) and nCr (combinations)
Read the result for your problem
Use the explanation to pick the right one
Calculates permutations (nPr) and combinations (nCr)
From n (total items) and r (chosen items)
Clear results for probability and statistics
Explains when to use each
Runs in your browser, nothing is uploaded
Free, with no signup and no limit on problems
Solving permutation and combination problems
Probability and statistics homework
Counting arrangements or selections
Checking nPr / nCr values
Ask 'does order matter?', yes = permutation (nPr), no = combination (nCr)
nCr is always ≤ nPr because it ignores the duplicate orderings permutations count
Passwords/rankings = permutations; hands/groups/selections = combinations
Common questions about this tool, its workflow, and what to expect before you use it.
No ratings yet. Be the first to say how Permutation & Combination worked for you.
Reviews appear here once our team has read them, so everything you see is from someone who signed in and used the tool.
Get notified about new tools, features, and tips. No spam, unsubscribe anytime.
Calculate logarithms with any base including ln, log10 & log2.
Open toolFull scientific calculator with trig, logs, factorial, memory, history & full keyboard support.
Open toolFind the grade you need on the final exam, or track your weighted course grade by category.
Open toolBalance any chemical equation instantly with the smallest whole-number coefficients & an element check.
Open toolTrack assignments & exams with due-date countdowns, priorities and progress, saved in your browser.
Open toolMeasure your reading speed (WPM) with comprehension checks and an RSVP speed-reading trainer.
Open toolUnscramble academic words across subjects with hints, a timer, streaks & saved high scores.
Open toolCalculate your Grade Point Average with course credits & grade scale.
Open toolWriting a roundup or tutorial? Embed the live Permutation & Combination so readers use it right on your page, or drop in a ready-made card that links to it. Free to use, always.
Preview
Calculate P(n,r) and C(n,r) with step-by-step formulas.
Use Permutation & Combination free →Live tool (iframe)
Readers use the real, working tool right on your page, with a small credit line underneath.
Embed card (HTML)