Calculators Browse A–Z Tax & Salary Property Guides

Tax year: 2026/27

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Maths, Science & Engineering Calculators

Graphing, calculus, matrices, statistics, networking, electrical and lab calculators.

Graphing CalculatorPlot up to four functions, zoom and read values off the graph.3D Graphing CalculatorDraw a 3D surface z = f(x, y) and rotate it to see its shape.Derivative CalculatorDifferentiate a function and evaluate the slope and tangent line at a point.Integral CalculatorWork out a definite integral and the area under a curve.Matrix CalculatorDeterminant, inverse, transpose, rank and matrix arithmetic.Statistics CalculatorMean, median, mode, standard deviation, quartiles and more from your data.Complex Number CalculatorAdd, multiply, divide and raise complex numbers, with polar form.Binary CalculatorBinary arithmetic, bitwise operations and conversions to decimal and hex.Subnet CalculatorNetwork, broadcast, host range and mask for any IPv4 address and prefix.Voltage Drop CalculatorVoltage drop for a cable run, checked against BS 7671 limits.Three-Phase Power CalculatorConvert between three-phase current, kW, kVA and kVAr.Battery CalculatorHow long a battery will run a load, in hours and minutes.Moment of Inertia CalculatorSecond moment of area and section modulus for beams and tubes.Molarity CalculatorMass, molarity and volume of a solution, plus C₁V₁ = C₂V₂ dilutions.Error Propagation CalculatorCombine measurement uncertainties through any formula.Sample Size CalculatorHow many responses you need for a survey's confidence and margin of error.Basic CalculatorA simple online calculator for adding, subtracting, multiplying and dividing.Fraction CalculatorAdd, subtract, multiply, divide and simplify fractions and mixed numbers.Triangle CalculatorSolve any triangle from three sides, two sides and an angle, or two angles and a side.Volume CalculatorVolume of a cube, cuboid, cylinder, cone, sphere and more, with litres.Surface Area CalculatorTotal surface area of 3D shapes, from cubes to cones.Area CalculatorArea and perimeter of rectangles, triangles, circles and other 2D shapes.Circle CalculatorRadius, diameter, circumference and area from any one of them.Pythagorean Theorem CalculatorFind the missing side of a right-angled triangle with a² + b² = c².Right Triangle CalculatorSolve a right-angled triangle from two sides or a side and an angle.Slope CalculatorSlope, equation of the line, angle and distance between two points.Distance CalculatorDistance between two points in 2D, 3D or on the Earth's surface.Random Number GeneratorPick random whole numbers or decimals in any range.Number Sequence CalculatorFind the nth term and sum of a sequence, or the pattern in your numbers.Percent Error CalculatorHow far a measured value is from the true value, as a percentage.Exponent CalculatorRaise a number to any power, or find the exponent.Log CalculatorLogarithms in base 10, e, 2 or any base.Root CalculatorSquare roots, cube roots and nth roots, with simplified surds.Half-Life CalculatorAmount remaining, half-life or time from exponential decay.Quadratic Formula CalculatorSolve ax² + bx + c = 0 with the quadratic formula.Probability CalculatorProbability of A and B, A or B, neither, and repeated events.Permutation and Combination CalculatornCr and nPr, with and without repetition.Z-score CalculatorZ-score, percentile and probabilities for a normal distribution.Confidence Interval CalculatorConfidence interval for a mean or a proportion.P-value CalculatorP-value from a z, t, chi-square or F test statistic.Ratio CalculatorSimplify ratios, find missing values and share amounts in a ratio.Least Common Multiple CalculatorThe lowest common multiple of two or more numbers.Greatest Common Factor CalculatorThe greatest common factor (HCF) of two or more numbers.Common Factor CalculatorAll the factors two or more numbers share.Factor CalculatorAll the factors and factor pairs of a number.Prime Factorization CalculatorBreak a number into its prime factors, with a division ladder.Rounding CalculatorRound to decimal places, significant figures or the nearest 10, 100…Scientific Notation CalculatorConvert to and from scientific notation (standard form), and do sums.Big Number CalculatorExact arithmetic on whole numbers of any size.Long Division CalculatorLong division step by step, with the remainder and decimal.Base64 Encode and DecodeEncode text to Base64 or decode Base64 back to text.URL Encode and DecodePercent-encode text for URLs, or decode it back.Bandwidth CalculatorDownload times, data use and the speed you need.Roman Numeral ConverterConvert numbers to Roman numerals and back.Density CalculatorDensity, mass or volume from the other two.Mass CalculatorMass from density and volume, weight, or force and acceleration.Weight CalculatorWeight in newtons from mass, on Earth and other planets.Speed CalculatorSpeed, distance or time from the other two.Horsepower CalculatorHorsepower from torque and RPM, kilowatts, or work and time.Engine Horsepower CalculatorEstimate engine power from weight and quarter-mile results.Resistor CalculatorResistance and tolerance from a resistor's colour bands.Ohm's Law CalculatorVoltage, current, resistance and power from any two.Molecular Weight CalculatorMolar mass of any chemical formula, with percentages by element.Wind Chill CalculatorHow cold it feels with the wind.Heat Index CalculatorHow hot it feels when humidity is high.Dew Point CalculatorDew point from temperature and humidity.GDP CalculatorGDP by the expenditure method, per person and growth.