What format should I use?

Enter time as hours:minutes, e.g. 2:30 for 2 hours 30 minutes, or 0:45 for 45 minutes.

Why use decimal hours?

Decimal hours are easier for payroll and billing (e.g. 2.5 hours instead of 2h 30m).

Convert hours:minutes (e.g. 2:30) to decimal hours (e.g. 2.5) for payroll and time tracking.

Time (hours:minutes)

What format should I use?: Enter time as hours:minutes, e.g. 2:30 for 2 hours 30 minutes, or 0:45 for 45 minutes.
Why use decimal hours?: Decimal hours are easier for payroll and billing (e.g. 2.5 hours instead of 2h 30m).

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.

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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.