Cost (or amount) per one unit of quantity (e.g. $/kg, $/item).

Can quantity be zero?

No. Quantity must be greater than zero to avoid division by zero.

What units can I use?

Any. Enter numbers only; you can label results yourself (e.g. $/lb, $/hour).

Find the rate per single unit: enter quantity and total cost (or other measure) to get rate per unit.

Quantity (e.g. units, kg)

Total cost (or total amount)

What is unit rate?: Cost (or amount) per one unit of quantity (e.g. $/kg, $/item).
Can quantity be zero?: No. Quantity must be greater than zero to avoid division by zero.
What units can I use?: Any. Enter numbers only; you can label results yourself (e.g. $/lb, $/hour).

Celsius to Fahrenheit Converter

Convert Celsius to Fahrenheit and Fahrenheit to Celsius instantly. Free temperature converter.

Tip Calculator

Calculate tip and split the bill. Enter bill amount, tip percentage, and number of people.

Roman Numeral Converter

Convert numbers to Roman numerals and Roman numerals to numbers. Supports 1–3999.

Combinations Calculator

Calculate C(n,r) — the number of ways to choose r items from n without order. Uses n!/(r!(n-r)!).

Combinations with Replacement Calculator

Calculate the number of ways to choose r items from n with repetition allowed. Formula: C(n+r-1, r).

Even Permutations Calculator

Count how many permutations of n objects are even (expressible as an even number of swaps). For n ≥ 2, equals n!/2.