Math & geometry measurement tools
Math tools compute circle, triangle, and rectangle area, cylinder and sphere volume, Pythagorean hypotenuse, percentage change, ratios, averages, GPA, and grades. Each calculator is a dedicated URL so students and teachers can link a specific problem type.
Math & geometry calculators
CalculatorArea of a Circle CalculatorCompute circle area and circumference from radius or diameter.CalculatorArea of a Triangle CalculatorFind triangle area from base and height, or from three sides (Heron).CalculatorArea of a Rectangle CalculatorCalculate rectangle area and perimeter from length and width.CalculatorVolume of a Cylinder CalculatorFind cylinder volume and lateral area from radius and height.CalculatorVolume of a Sphere CalculatorCompute sphere volume and surface area from radius.CalculatorPythagorean Theorem CalculatorSolve for hypotenuse or a leg of a right triangle.CalculatorPercentage Change CalculatorMeasure percent increase or decrease from an old value to a new value.CalculatorRatio CalculatorSimplify a ratio A:B and scale it to a target part.CalculatorAverage CalculatorFind the mean of a list of numbers separated by commas.CalculatorGPA CalculatorEstimate a 4.0-scale GPA from credit hours and letter grades.CalculatorFinal Grade CalculatorFind the exam score you need to reach a target course grade.CalculatorFraction to Decimal CalculatorConvert a fraction n/d to a decimal and a percent.