GCF Calculator
How to Find GCF (Greatest Common Factor)
GCF is the largest integer that divides every input. Euclid’s algorithm, a 48-18-30 example and the free GCF calculator.
Calculator guides
Plain-English formulas, tables and examples for the searches people actually type — then a free tool to run your own numbers. Every guide matches a calculator on this site.
Showing 7–12 of 19 guides · Page 2
LCM Calculator
How to Find LCM (Least Common Multiple)
The least common multiple is the smallest number that every input divides. Here is the GCF formula, a 12-18-24 example and the free LCM calculator.
Percentage Calculator
How to Calculate a Percentage (Of, Is, and Change)
Percent means per hundred. Here are the three everyday formulas — of, is, and change — and when to use tip, discount or sales tax instead.
Age Calculator
How to Calculate Age in Years, Months and Days
People count age as whole birthdays, then leftover months and days. Here is how our age calculator does it, including February 29.
Area Calculator
How to Calculate Area of Shapes (With Formulas)
Area is the space inside a 2-D shape. Here are the formulas our area calculator uses, including parallelograms and circular sectors.
Volume Calculator
How to Calculate Volume of Common Shapes
Volume is length × width × height for a box — and πr²h for a cylinder. Here are the shapes our volume calculator supports.