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Combinations With Repetition Calculator

Combinations With Repetition Calculator for statistics practice, sequence review, and quick worksheet math when you want a fixed formula answer without improvising the math by hand.

Important Use Notice

Informational calculator only. Verify important outputs independently before legal, tax, medical, engineering, safety-critical, contractual, employment, or compliance use.

Estimate

Enter job values, review the estimate, then use the decision hints before ordering or quoting.

Estimate Results

Enter values to see the result.

Example

5, 3 gives Combinations 35.

Formula

count = (n + r - 1 choose r)

Treat repeated selections as a stars-and-bars counting problem and use the matching binomial coefficient.

This is different from ordinary combinations because repeats are allowed.

Check

Mixing units, scales, or coordinate conventions across n, r before calculating combinations.
Confirm that all inputs use the same unit system expected by the formula.

Next Step

FAQ

When should I keep more decimals for combinations with repetition calculator?

Keep more precision when the output will feed another formula, drawing, coordinate step, or comparison rather than being rounded once and left alone.