Percentage Calculator
Calculate percent of a number, part as percent of whole, percentage change, percentage-point difference, increase/decrease and whole-from-part.
Open calculatorWhat this category helps with
Math calculators help with questions where a number is useful but the assumptions matter. Start with the calculator closest to your question, then use the linked guide or formula page when units, rates, dates, local rules or source data could change the answer.
Best starting points
Rectangle Area Calculator
Calculate rectangle area from length and width.
Open calculatorSquare Area Calculator
Calculate square area from side length.
Open calculatorCircle Area Calculator
Calculate circle area from radius.
Open calculatorTriangle Area Calculator
Calculate triangle area from base and height.
Open calculatorTrapezoid Area Calculator
Calculate trapezoid area from two bases and height.
Open calculatorHow to choose the right calculator
- Use a broad calculator first when you need a quick estimate.
- Use a more specific calculator when rates, units, dates, eligibility or fees change the answer.
- Read assumptions before comparing results across calculators or external sources.
- For current-data topics, confirm the data source and date before relying on the result.
Calculators
Percentage Calculator
Calculate percent of a number, part as percent of whole, percentage change, percentage-point difference, increase/decrease and whole-from-part.
Open calculatorRectangle Area Calculator
Calculate rectangle area from length and width.
Open calculatorSquare Area Calculator
Calculate square area from side length.
Open calculatorCircle Area Calculator
Calculate circle area from radius.
Open calculatorTriangle Area Calculator
Calculate triangle area from base and height.
Open calculatorTrapezoid Area Calculator
Calculate trapezoid area from two bases and height.
Open calculatorParallelogram Area Calculator
Calculate parallelogram area from base and height.
Open calculatorEllipse Area Calculator
Calculate ellipse area from semi-major and semi-minor axes.
Open calculatorRectangle Perimeter Calculator
Calculate rectangle perimeter from length and width.
Open calculatorCircle Circumference Calculator
Calculate circumference from radius.
Open calculatorTriangle Perimeter Calculator
Calculate triangle perimeter from three side lengths.
Open calculatorCube Volume Calculator
Calculate cube volume from side length.
Open calculatorRectangular Prism Volume Calculator
Calculate box volume from length, width and height.
Open calculatorCylinder Volume Calculator
Calculate cylinder volume from radius and height.
Open calculatorSphere Volume Calculator
Calculate sphere volume from radius.
Open calculatorCone Volume Calculator
Calculate cone volume from radius and height.
Open calculatorPyramid Volume Calculator
Calculate pyramid volume from base area and height.
Open calculatorCube Surface Area Calculator
Calculate cube surface area from side length.
Open calculatorSphere Surface Area Calculator
Calculate sphere surface area from radius.
Open calculatorCylinder Surface Area Calculator
Calculate closed cylinder surface area from radius and height.
Open calculatorFraction to Percent Calculator
Convert a fraction to a percentage.
Open calculatorPercent to Decimal Calculator
Convert a percentage to a decimal.
Open calculatorDecimal to Percent Calculator
Convert a decimal to a percentage.
Open calculatorRatio to Percent Calculator
Convert part and whole values to a percentage.
Open calculatorExponent Calculator
Calculate a base raised to an exponent.
Open calculatorSquare Root Calculator
Calculate the square root of a non-negative number.
Open calculatorLogarithm Calculator
Calculate logarithm with a chosen base.
Open calculatorAbsolute Difference Calculator
Calculate the absolute difference between two numbers.
Open calculatorScientific Calculator
Perform common scientific operations on a single value.
Open calculatorFraction Calculator
Add two fractions and return a decimal result.
Open calculatorTriangle Calculator
Calculate triangle area from base and height.
Open calculatorVolume Calculator
Calculate rectangular prism volume.
Open calculatorRandom Number Generator
Generate a random number between a minimum and maximum.
Open calculatorNumber Sequence Calculator
Find the nth term of an arithmetic sequence.
Open calculatorPercent Error Calculator
Calculate percent error between measured and accepted values.
Open calculatorQuadratic Formula Calculator
Calculate the real roots of ax^2 + bx + c when they exist.
Open calculatorSlope Calculator
Calculate slope from two points.
Open calculatorRatio Calculator
Convert two numbers into a simplified ratio.
Open calculatorCircle Calculator
Calculate circle area and circumference from radius.
Open calculatorSurface Area Calculator
Calculate rectangular prism surface area.
Open calculatorPythagorean Theorem Calculator
Calculate hypotenuse from two right-triangle legs.
Open calculatorRight Triangle Calculator
Calculate hypotenuse and area of a right triangle.
Open calculatorRoot Calculator
Calculate nth root of a number.
Open calculatorLeast Common Multiple Calculator
Calculate least common multiple of two integers.
Open calculatorGreatest Common Factor Calculator
Calculate greatest common factor of two integers.
Open calculatorFactor Calculator
Count factors of a positive integer.
Open calculatorRounding Calculator
Round a number to a selected number of decimal places.
Open calculatorMatrix Calculator
Calculate determinant of a 2 by 2 matrix.
Open calculatorScientific Notation Calculator
Convert a number to scientific-notation components.
Open calculatorBig Number Calculator
Estimate powers for large-number planning.
Open calculatorPrime Factorization Calculator
Count prime factors of a positive integer.
Open calculatorCommon Factor Calculator
Calculate common factor count for two integers.
Open calculatorBasic Calculator
Perform basic arithmetic on two numbers.
Open calculatorLong Division Calculator
Calculate quotient and remainder for integer division.
Open calculatorRoman Numeral Converter
Convert an integer from 1 to 3999 into a Roman numeral.
Open calculator