Permutations Calculator
Permutations is evaluated from Total Items, Items to Arrange and Allow Repetition?. The calculation reports Permutations P, Combinations C and Circular Permutations.
Results
About the Permutations Calculator
The calculator uses a multi formula configuration. Each reported value is read as a direct evaluation of the stored rules with the declared field formats and units.
Formula basis:
P(n,r) = n! / (n - r)!
P with repetition = nʳ
Circular P(n) = (n - 1)!
Interpret the outputs in the order shown by the result fields. Optional inputs affect only the outputs that depend on those variables.
Formula & How It Works
The calculation applies the following relations exactly as recorded in the metadata: P(n,r) = n! / (n - r)! P with repetition = nʳ Circular P(n) = (n - 1)! Each output field is produced by substituting the supplied inputs into the relevant relation and then applying the declared rounding or text format.
Worked Examples
Example 1: 4-Digit PIN (with repetition)
Inputs
With Total Items = 10, Items to Arrange = 4 and Allow Repetition? = yes as the stated inputs, the result is Permutations P = 10,000, Combinations C = 210 and Circular Permutations = 0. Each value corresponds to the declared output fields.
Example 2: Race Finishing Order — Top 3 of 8
Inputs
With Total Items = 8, Items to Arrange = 3 and Allow Repetition? = no as the stated inputs, the result is Permutations P = 336, Combinations C = 56 and Circular Permutations = 0. Each value corresponds to the declared output fields.
Example 3: Seating 6 People at a Round Table
Inputs
With Total Items = 6, Items to Arrange = 6 and Allow Repetition? = no as the stated inputs, the result is Permutations P = 720, Combinations C = 1 and Circular Permutations = 120. Each value corresponds to the declared output fields.
Example 4: License Plate — Letters and Digits
Inputs
With Total Items = 26, Items to Arrange = 3 and Allow Repetition? = yes as the stated inputs, the result is Permutations P = 17,576, Combinations C = 2,600 and Circular Permutations = 0. Each value corresponds to the declared output fields.
Common Use Cases
- Count ways to arrange letters in a word
- Find number of race finishing orders
- Calculate PIN and password combinations
- Count ways to assign seats in a row