Maths Calculators

Percentage Calculator

Calculate any percentage instantly — 4 types: find % of a number, what % one number is of another, what the original number was, or increase/decrease by %.

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Percentage Change Calculator

Calculate percentage increase or decrease between two values. Find out how much something has changed as a percentage.

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Average (Mean) Calculator

Calculate the mean, median, mode, range, and standard deviation of any set of numbers. Paste in up to 100 values.

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Quadratic Equation Solver

Solve any quadratic equation ax² + bx + c = 0 instantly. Shows full working using the quadratic formula.

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Circle Calculator

Calculate the area, circumference, diameter, and radius of any circle. Enter any one measurement to find all the others.

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Triangle Calculator

Calculate the area, perimeter, angles, and height of any triangle. Works for right-angled, equilateral, isosceles, and scalene triangles.

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Ratio Calculator

Simplify ratios, scale ratios, and solve proportions. Works for any ratio — cooking, mixing, scale models, map distances and more.

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Fraction Calculator

Add, subtract, multiply, and divide fractions. Simplify fractions and convert between fractions, decimals, and percentages.

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Prime Number Checker

Check if any number is prime, find prime factors, and generate a list of primes up to any limit.

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LCM and GCD Calculator

Calculate the Lowest Common Multiple (LCM) and Greatest Common Divisor (GCD) of any two or three numbers.

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Permutations & Combinations Calculator

Calculate permutations (nPr) and combinations (nCr) for any values of n and r. Understand when to use each and see the factored working.

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Binary, Decimal & Hex Converter

Convert between binary, decimal, hexadecimal, and octal number systems. See the full conversion with step-by-step working.

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Slope, Gradient & Angle Calculator

Calculate slope, gradient, angle, and equation of a line from two points or from rise and run. Convert between degrees, percent grade, and ratio.

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Scientific Notation Calculator

Convert numbers to and from scientific notation. Perform multiplication, division, addition, and subtraction with numbers in scientific notation.

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Standard Deviation Calculator

Calculate mean, median, mode, variance, and standard deviation for any data set. Enter up to 50 numbers for a full statistical summary.

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Probability Calculator

Calculate probability for single events, combined events (AND/OR), conditional probability, and complement. With worked examples.

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Logarithm Calculator

Calculate logarithms in any base — log₁₀, ln (natural log), log₂, and custom bases. Also handles antilog and change of base.

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