Type a list of items, choose how many go in each group, and get every possible combination where order does not matter. Turn on repetition to allow an item more than once, then copy the list or download it as CSV.
Last updated:
Separate with commas, spaces or new lines, or type a word to use its letters
Up to 20,000 rows; the count is always exact
Enter your values to see the result.
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How to use the Combinations Generator
Enter your items separated by commas, spaces or new lines, or type a word such as ABCDE to use its letters.
Set k, the number of items in each combination.
Tick Allow repetition if an item may appear more than once in a group (for example scoops of the same ice cream flavor).
Press Generate. The exact count appears at the top and the combinations are listed in a table.
Copy or download: Copy results copies the full list, one combination per line, and Download CSV saves the table.
The combinations formula
A combination is a selection of k items from a set of n where the order of the selected items does not matter. The number of such selections is the binomial coefficient:
C(n, k) = n! ÷ (k! × (n − k)!)
The k! in the denominator removes the orders: each group of k items can be arranged in k! ways, and all of those arrangements count as one combination. When repetition is allowed, the count becomes C(n + k − 1, k), which is the "stars and bars" result for distributing k picks among n kinds.
How fast combinations grow
n items
k = 2
k = 3
k = 5
k = n/2
All subsets (2ⁿ)
5
10
10
1
10 (k = 2)
32
8
28
56
56
70
256
10
45
120
252
252
1,024
12
66
220
792
924
4,096
20
190
1,140
15,504
184,756
1,048,576
52
1,326
22,100
2,598,960
about 4.96 × 10¹⁴
about 4.5 × 10¹⁵
The 52, 5 entry is the number of different 5-card hands from a standard deck. Notice the symmetry C(n, k) = C(n, n − k): choosing 3 of 10 to include is the same as choosing 7 of 10 to leave out.
Everyday uses
Menus and outfits: every pair of side dishes, every 3-topping pizza, every 2-shirt packing choice.
Teams and committees: all possible groups of 4 from a class of 10, to check fairness or plan rotations.
Testing: list every pair of settings or features to cover in software or product tests.
Homework: verify a counting answer by seeing the actual list, not just the number.
Tip: if you need every possible group size at once (the power set), look at the counts table under the results, which shows how many combinations exist for every k.
Frequently asked questions
What is the difference between a combination and a permutation?
In a combination the order does not matter, so {A, B} and {B, A} are the same group. In a permutation the order matters, so AB and BA are different. Choosing 2 of A, B, C gives 3 combinations (AB, AC, BC) but 6 permutations (AB, BA, AC, CA, BC, CB).
How many combinations are there?
Without repetition the count is C(n, k) = n! ÷ (k! × (n − k)!), often read as "n choose k". For example, choosing 3 of 5 items gives 5! ÷ (3! × 2!) = 10 combinations. The generator shows this formula with your numbers.
What does combinations with repetition mean?
It allows the same item to be picked more than once, like choosing 3 scoops from 4 flavors where two scoops can be vanilla. The count is C(n + k − 1, k); for 4 flavors and 3 scoops that is C(6, 3) = 20.
What happens if my list has duplicate items?
Identical items are treated as the same thing, so a combination is only listed once. Choosing 3 letters from BANANA gives 6 distinct groups (AAA, AAN, ANN, BAA, BAN, BNN) rather than the 20 you would get if every letter were different.
Why does it only list part of the results?
The number of combinations grows very quickly: choosing 10 of 30 items already gives 30,045,015 groups. To keep your browser responsive the generator lists up to 20,000 (1,000 by default) while still showing the exact total count.
In what order are the combinations listed?
In lexicographic order of the positions you typed the items in, and every combination keeps that order. With A, B, C, D the 2-combinations come out as AB, AC, AD, BC, BD, CD.
Is my list sent anywhere?
No. All combinations are generated by JavaScript in your browser, and nothing you type is uploaded.
Are all the tools on FreeToolCabin tested for quality and accuracy?
Yes! Every tool on our site undergoes automated Q/A testing in real browser environments to ensure high precision, correct output, and zero errors. If you happen to spot a bug or have a suggestion, please contact us at [email protected] and our team will review it right away.