GALAXY OF TOOLS

MATH SECTOR · 31 TOOLS

Free Math Calculators Online

Percentages, fractions, equations, statistics and geometry, solved instantly. 31 free tools, no sign-up.

Everyday maths9

Percentage CalculatorWork out percentages, percentage change, increases and decreases — with the formula shown.Math CalculatorsOnline CalculatorA clean everyday calculator with big keys, memory, a history tape and full keyboard support.Math CalculatorsPercentage Change CalculatorPercentage change from old to new, percentage difference, percentage points and the original value before a change.Math CalculatorsAverage CalculatorFind the mean, median, mode, range and more for any list of numbers — or a weighted average.Math CalculatorsLarge CalculatorA big-button, high-contrast calculator with a giant display and optional spoken results — easy on the eyes.Math CalculatorsFraction CalculatorFraction maths with steps: add, subtract, multiply, divide, simplify, convert to decimal or %, print a chart.Math CalculatorsRatio CalculatorSolve proportions, simplify ratios, split an amount in a ratio and convert ratios to fractions or percentages.Math CalculatorsRounding CalculatorRound to decimal places, significant figures or any multiple, with seven rounding modes and exact decimals.Math CalculatorsSignificant Figures CalculatorCount sig figs digit by digit, round to n significant figures and do + − × ÷ with the chemistry sig-fig rules.Math Calculators

Algebra & numbers10

Scientific CalculatorA full scientific calculator with trig, logs, powers, roots, factorials, memory and history.Math CalculatorsSquare Root CalculatorSquare, cube and nth roots to 50 decimal places, simplest radical form, and printable roots tables.Math CalculatorsQuadratic Equation SolverSolve ax² + bx + c = 0 with exact and decimal roots, step-by-step working and a plotted parabola.Math CalculatorsExponent CalculatorRaise any number to any power — exact big results, negative and fractional exponents, or solve for the exponent or base.Math CalculatorsLCM and GCD CalculatorFind the LCM and GCD (HCF) of two or more numbers, with prime factor tables and Euclid’s algorithm.Math CalculatorsLogarithm CalculatorFind log, ln and log₂ of any number in any base, antilogs, or solve bʸ = x — with change-of-base steps.Math CalculatorsPermutation and Combination CalculatorCount arrangements and selections — nPr, nCr, with or without repetition — exactly, with factorial steps.Math CalculatorsScientific Notation ConverterConvert numbers to and from scientific, E, engineering and SI-prefix notation, with sig-fig control.Math CalculatorsPrime Number CheckerCheck if a number is prime, factorise it, find the next and previous prime, or list every prime in a range.Math CalculatorsFactorial CalculatorExact factorials up to 10,000! with every digit, trailing zeros, digit count, n!! and the gamma function.Math Calculators

Geometry4

Area CalculatorFind the area of 13 shapes, including a 4-sided plot, with the formula, a diagram and every common unit.Math CalculatorsPythagorean Theorem CalculatorSolve any side of a right triangle, plus angles, area and perimeter, with a scale drawing and triple check.Math CalculatorsVolume CalculatorFind the volume and surface area of 10 solids, with formulas, a diagram and results in litres and gallons.Math CalculatorsTriangle CalculatorSolve any triangle from three known values: all sides and angles, area, heights, medians, radii and a scale drawing.Math Calculators

Statistics, probability & numerals4

Probability CalculatorSingle and combined events, Bayes, binomial “at least” questions and odds — exact answers with the working shown.Math CalculatorsNumber to Words ConverterSpell numbers in English or Hindi, write cheque amounts, convert lakh and crore to million, or put a date in words.Math CalculatorsStandard Deviation CalculatorFind sample and population standard deviation, variance, mean and standard error, with a step table.Math CalculatorsRoman Numeral ConverterConvert numbers and years to Roman numerals and back, with strict validation and a place-by-place breakdown.Math Calculators

Physics & electrical4

Speed CalculatorFind speed, distance or travel time, average speed over several legs and your arrival time — with every step.Math CalculatorsOhm’s Law CalculatorEnter any two of V, I, R and P to get the other two, plus series/parallel resistors and E12/E24/E96 pairs for a target.Math CalculatorsWatt CalculatorWatts from volts and amps for DC, single- and three-phase AC, amps and volts from watts, VA ↔ W and energy cost.Math CalculatorsVoltage CalculatorFind volts from current, resistance or power, the voltage drop along a cable, and voltage-divider outputs.Math Calculators

Math calculators that show the working

Some sums are too fiddly for mental arithmetic and too quick to justify opening a spreadsheet. What is 18% of 2,450? What is 3/8 plus 5/12? How do you solve 2x² − 7x + 3 = 0? These free math calculators answer questions like these instantly and, just as importantly, show the formula or the steps, so you can check the result and learn the method instead of copying a number, which helps when a teacher wants to see the working too.

The collection runs from everyday arithmetic to school and college topics. The percentage calculator handles discounts, marks and growth, the fraction calculator simplifies and works with mixed numbers, the scientific calculator covers trigonometry, logs and powers, and the quadratic equation solver gives exact roots with a plotted parabola. Statistics, geometry, number theory and conversions such as Roman numerals each have dedicated tools as well. You will also find tools for exponents, logarithms, factorials, ratios, rounding and scientific notation, each focused on doing one job clearly.

Students use them to check homework and revise for board exams, SATs or GCSEs, teachers use them to prepare worked examples, and parents use them to make sense of the methods their children bring home. Everything is calculated in your browser, so answers appear as you type, with no sign-up and nothing sent anywhere. For money and measurements, the finance calculators and unit converters work the same way.

Finding the right calculator

A few tools overlap, so here is how to pick the one that fits your question:

  • Percentage or percentage change. Use the percentage calculator for “what is X% of Y” and “X is what percent of Y”. Use the percentage change calculator to compare an old and a new value, such as a price rise or a drop in marks.
  • Average or spread. The average calculator gives the mean, median, mode and range. When you need to know how spread out the numbers are, the standard deviation calculator shows sample and population results with a step table.
  • LCM or GCD. Adding fractions needs a common denominator, which is the least common multiple; simplifying a fraction needs the greatest common divisor. The LCM and GCD calculator finds both with prime factor tables.
  • Area or volume. Flat shapes such as a floor or a plot of land need the area calculator; solids such as a water tank or a box need the volume calculator.

Getting answers you can trust

A calculator is only as good as the numbers and settings you give it. These habits help:

  • Mind the order of operations. The scientific calculator follows standard precedence (brackets, powers, multiplication and division, then addition and subtraction), so add brackets when you mean something else.
  • Check whether you are in degrees or radians before using sin, cos or tan. It is the most common cause of a “wrong” trigonometry answer.
  • Round only at the end. Rounding intermediate results adds error, so keep full precision and round the final answer to the places your question asks for.
  • For cheques and legal documents, the number to words converter spells out amounts in the international system or the Indian lakh and crore system.

Math Calculators: frequently asked questions

How do I calculate a percentage of a number?

Multiply the number by the percentage and divide by 100. For example, 18% of 2,450 is 2,450 × 18 ÷ 100 = 441.

What is the difference between sample and population standard deviation?

Population standard deviation divides by n and describes a complete data set. Sample standard deviation divides by n − 1 to correct for working from a subset, so it comes out slightly larger.

Do these calculators show step-by-step solutions?

Many do. The fraction, quadratic, square root, LCM and GCD, logarithm and standard deviation tools show the working alongside the answer, so you can follow the method.

How do I check whether a large number is prime?

Use the prime number checker. It tests the number, shows its prime factorisation if it is not prime, and finds the nearest primes on either side.

What is the difference between decimal places and significant figures?

Decimal places count digits after the decimal point, while significant figures count from the first non-zero digit. So 0.004567 is 0.00 to two decimal places but 0.0046 to two significant figures.

Can I use the scientific calculator for exam practice?

Yes. It covers the functions of a typical school scientific calculator, including trigonometry, logarithms, powers, roots and factorials. Check your exam rules, though, because most exams allow only approved handheld calculators.