Permutation Calculator (nPr)
Calculate the number of permutations (nPr) for arranging r items from n items.
The Permutation Calculator computes the number of ways to arrange r items from a set of n items where order matters. This is written as P(n,r) or nPr.
Enter n (total items) and r (items to arrange). The formula is nPr = n! / (n-r)!. Permutations are always greater than or equal to combinations because different orderings count as distinct arrangements.
Permutations are used in password calculations, race finishing orders, seating arrangements, and any scenario where the sequence of selection matters.
Frequently Asked Questions
When do I use permutations instead of combinations?
Use permutations when order matters (1st, 2nd, 3rd place in a race). Use combinations when order does not matter (choosing team members).
What is the relationship between nPr and nCr?
nPr = nCr * r!. Permutations equal combinations multiplied by the number of ways to arrange the chosen items.
How many 4-digit PIN codes are possible?
P(10,4) = 5,040 if no digit repeats. With repeats allowed, it is 10^4 = 10,000.