Mathlean · Online math workspace
Combinations and binomial coefficient calculator
Count selections of k objects from n distinct objects when order does not matter.
How to use this calculator
Edit the top number n and bottom number k. The starter chooses 3 from 10, giving 120 selections.
Tap the math below to edit it and see the result. Once a result is ready, press Tab on a hardware keyboard to accept it. Outside a matrix, Return completes the line; the phone math keyboard has the same Return action.
Try it here
Interactive tools require JavaScript. You can read the guide and example without it.
What to know
This counts selections without replacement. Ordered arrangements belong to the permutations tool.
Mathlean combines visual mathematical input with computation and canvas tools. Results depend on the expression and available engine support; check important answers independently.