Percentage
Calculate what x% of y is, what percentage a is of b, and the percentage change from A to B.
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Math calculators
Percentages, trigonometry, Pythagoras, quadratic equations, logarithms, combinatorics (nCr/nPr), GCD/LCM, circles and Heron’s triangle formula.
Percentage change
Calculate the percentage increase or decrease from a starting value to a new value.
Open calculatorTrigonometry (sin, cos, tan)
Calculate sine, cosine, tangent and radian measure for an angle in degrees.
Open calculatorPythagorean theorem
Enter any two sides of a right triangle and the calculator solves for the third side and triangle area.
Open calculatorQuadratic equation
Find the discriminant (Δ) and real roots (x₁, x₂) of a quadratic equation ax² + bx + c = 0.
Open calculatorLogarithm
Calculate log_b(x) for any valid base, alongside the natural logarithm (ln) and common base-10 logarithm (log₁₀).
Open calculatorCombinatorics (n!, nPr, nCr)
Calculate factorial (n!), permutations without repetition (nPr) and combinations (nCr) for whole numbers.
Open calculatorGCD and LCM
Find the greatest common divisor (GCD) and least common multiple (LCM) of two integers.
Open calculatorCircle area & circumference
Calculate diameter, circumference and area of a circle from its radius.
Open calculatorTriangle area (Heron’s formula)
Calculate the area and semi-perimeter of any valid triangle from the lengths of its three sides.
Open calculatorSnell’s law of refraction
Calculate the angle of refraction across an optical boundary (n₁, n₂) or check for total internal reflection.
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