Mathematics
Arithmetic, algebra, geometry and number theory tools.
Everything from arithmetic you would rather not do by hand to geometry, algebra and number theory. Some of these are quick utilities you use once and close; others show the working so you can follow the method rather than just take the answer.
Where a calculator uses a named formula — Heron, Pythagoras, the quadratic formula — the page states it and works through an example with real numbers.
25 calculators in this category
Basic Calculator
Perform simple arithmetic calculations with ease.
Percentage Calculator
Calculate percentages, increases, decreases, and more.
Scientific Calculator
Advanced calculator with trigonometry, logarithms, and constants.
Fraction Calculator
Add, subtract, multiply, and divide fractions with step-by-step results.
Area Calculator
Calculate areas of circles, rectangles, triangles, and more.
Volume Calculator
Calculate volumes of spheres, cylinders, cones, and other 3D shapes.
Average Calculator
Calculate mean, median, mode, and range of any set of numbers.
GCD & LCM Calculator
Find the Greatest Common Divisor and Least Common Multiple.
Exponent Calculator
Calculate powers, roots, and exponential expressions.
Random Number Generator
Generate random numbers, integers, or sequences within any range.
Rounding Calculator
Round numbers to any decimal place or significant figures.
Triangle Calculator
Solve any triangle — sides, angles, area using law of sines/cosines.
Quadratic Equation Solver
Solve ax²+bx+c=0, find roots, discriminant, and vertex.
Matrix Calculator
Add, subtract, multiply matrices; find determinant and transpose.
Distance Calculator
Distance between two points in 2D or 3D space.
Slope Calculator
Find slope, midpoint, distance, angle, and line equation.
Factor Calculator
Find all factors and prime factorization of any integer.
Algebra Calculator
Solve linear equations ax+b=c or 2×2 systems of equations.
Logarithm Calculator
Calculate log in any base — log₁₀, ln, log₂, or custom.
Circle Calculator
Find radius, diameter, circumference, and area of a circle.
Right Triangle Calculator
Solve right triangles using Pythagorean theorem and trigonometry.
Sequence Calculator
Arithmetic and geometric sequences — terms, sum, nth term.
Roman Numeral Converter
Convert between Arabic numbers and Roman numerals (1–3999).
Concrete Calculator
Calculate concrete volume for slabs, columns, and footings.
Binary Calculator
Arithmetic and bitwise operations in binary, octal, decimal, or hex.
Which calculator do I need?
Start from the job rather than the tool.
- Do ordinary arithmetic — Basic Calculator or Scientific Calculator
- Work with percentages, increases and discounts — Percentage Calculator
- Find the area or volume of a shape — Area Calculator or Volume Calculator or Circle Calculator
- Solve a triangle — Triangle Calculator or Right Triangle CalculatorRight Triangle for anything involving a 90° corner; Triangle for the rest.
- Solve an equation — Algebra Calculator or Quadratic Equation Solver
- Simplify or compare fractions — Fraction Calculator or GCD & LCM Calculator
- Break a number into its factors — Factor Calculator
- Work with powers, roots and logs — Exponent Calculator or Logarithm Calculator
- Find the gradient or distance between two points — Slope Calculator or Distance Calculator
- Estimate materials for a building job — Concrete Calculator
- Convert between number systems — Binary Calculator or Roman Numeral Converter
What these calculators have in common
Assumptions worth knowing before you rely on any result here.
Order of operations decides the answer
Brackets, then indices, then multiplication and division, then addition and subtraction. 2 + 3 × 4 is 14, not 20. When an expression gets long, add brackets even where they are technically unnecessary — they cost nothing and remove the ambiguity.
Rounding early changes the result
Carry full precision through the working and round only the final answer. Rounding an intermediate value to two decimals and then multiplying by a large number can shift the result noticeably.
Degrees and radians are not interchangeable
Trigonometric functions give a plausible but wrong answer in the wrong mode. Geometry problems are usually degrees; anything involving π or calculus is radians. Checking that sin 30 reads 0.5 confirms the mode in a second.