Math Calculators

Algebra, geometry, trigonometry, statistics, and everyday math in one place: solve equations, work out areas and angles, run probability and standard deviation, handle fractions and percentages, and more than a hundred tools besides.

Every calculator is free, shows the formula with a worked example, and many include a labelled diagram so you can see what the numbers mean. Browse by topic below or search by name.

📐 Geometry 7

Circle CalculatorEnter radius, diameter, circumference or area and get all four circle measurements.Cone CalculatorGet volume, slant height, lateral and total surface area and base area from base radius and height.Cylinder CalculatorGet volume, lateral and total surface area, base area and circumference from radius and height.Pythagorean Theorem CalculatorFind the hypotenuse or a missing leg of a right triangle, plus area and perimeter.Regular Polygon CalculatorGet area, perimeter, interior and exterior angles, apothem and circumradius from sides and side length.Sphere CalculatorGet volume, surface area, diameter and great-circle circumference from radius or diameter.Triangle Area CalculatorFind triangle area from base and height, three sides by Herons formula, or two sides and the included angle.

📐 Algebra 7

Distance Formula CalculatorFind straight-line distance between two points in 2D or 3D, with deltas and midpoint.Exponent CalculatorRaise any base to a whole, negative or fractional power, with scientific notation and reciprocal forms.Logarithm CalculatorCompute the log of any positive number in any base, plus natural, common and binary logs.Midpoint CalculatorFind the point halfway between two coordinates, plus the segment distance and slope.Quadratic Formula CalculatorSolve any quadratic ax^2+bx+c=0 for real or complex roots, with discriminant, vertex and axis of symmetry.Slope CalculatorGet slope, angle of incline, y-intercept, line equation and distance from two points.System of Equations CalculatorSolve two linear equations in x and y by Cramers rule, with determinant and solution type.

📐 Trigonometry 6

Angle Converter CalculatorConvert between degrees, radians and gradians, plus turns and multiples of pi.Arc Length CalculatorGet arc length, sector area and chord from a radius and central angle.Law of Cosines CalculatorSolve a triangle from two sides and the included angle, or all three sides, using the law of cosines.Law of Sines CalculatorSolve a triangle from two angles and a side using the law of sines.Right Triangle CalculatorSolve all sides and angles of a right triangle from any two knowns, plus area and perimeter.Trig Function CalculatorGet sine, cosine, tangent, cosecant, secant and cotangent of any angle in degrees or radians.

📐 Statistics & Probability 6

Combinations and Permutations CalculatorCompute combinations nCr, permutations nPr and factorials from n and r.Mean Median Mode CalculatorPaste a list of numbers for mean, median, mode, range, count, sum, min and max.Probability CalculatorCombine two independent events for AND, OR, neither, exactly one, and complement probabilities.Standard Deviation CalculatorSample and population standard deviation, variance, mean and sum of squares from a data set.Weighted Average CalculatorEnter values and matching weights to get the weighted mean, with the simple mean for comparison.Z-Score CalculatorFind how many standard deviations a value is from the mean, plus percentile and tail probabilities.

📊 Number Theory 5

Base Converter CalculatorConvert numbers between any bases 2 to 36, with binary, octal, decimal and hexadecimal always shown.GCD and LCM CalculatorFind the greatest common divisor and least common multiple of two or more whole numbers.Modulo CalculatorFind a mod n, the floored quotient and whether it divides evenly.Prime Factorization CalculatorBreak any number into prime factors in exponent form, with divisor count, sum and a prime check.Prime Number CheckerTest whether a number is prime, see its smallest divisor, and the nearest primes above and below.

📐 Sequences & Series 4

Arithmetic Sequence CalculatorFind any term and the sum of the first n terms from the first term and common difference.Factorial CalculatorCompute n! exactly or in scientific form, with the digit count and number of trailing zeros.Fibonacci CalculatorGet the nth Fibonacci number, the sequence, the sum, and the golden ratio, with exact big-number math.Geometric Sequence CalculatorFind any term, the sum of n terms, and the infinite sum from the first term and common ratio.

📐 Specialty & Other Tools 2

Age CalculatorCalculate an exact age from a birthdate in years, months and days.Date CalculatorAdd or subtract days, weeks, months or years from a date.

🔢 Arithmetic & Percentages 1

Percentage CalculatorHome » Math CalculatorsMATHEMATICS Work out any percentage in one place. Pick the type of calculation, enter your two numbers, […]

📏 Conversions 1

Unit Conversion CalculatorHome » Math CalculatorsMATHEMATICSConvert between units of length, weight, volume, temperature, area, speed, time, data, pressure, and energy. Pick a […]

What you can calculate here

The library covers school and everyday math end to end. Algebra tools solve equations, simplify expressions, and handle exponents and logarithms. Geometry tools find area, perimeter, volume, and surface area for common shapes. Trigonometry tools work out sides and angles using the law of sines, the law of cosines, and the Pythagorean theorem. Statistics tools cover mean, median, standard deviation, probability, and combinations. There are also fraction, percentage, ratio, and rounding tools for quick everyday sums.

Who these calculators are for

Students use them to check homework and follow the working, not just the answer. Teachers and tutors use the diagrams to explain a concept quickly. DIYers and shoppers reach for the percentage, ratio, and area tools for real-world sums. Anyone who wants a fast, reliable result without setting up a spreadsheet will find the right tool here.

Getting accurate results

A few quick habits keep your answers right:

  • Enter angles in the units the tool expects. Most state degrees or radians next to the field.
  • For geometry, double-check which measurement you have: radius or diameter, edge or diagonal.
  • With statistics, make sure you are using the right population or sample formula for your data.
  • Results are rounded for readability while the tool keeps full precision internally.

Frequently asked questions

Are these calculators free?

Yes. Every math calculator here is free, with no account and no usage limit.

Do the tools show the steps?

Many show the formula and a worked example so you can follow the method, and several include a labelled diagram of the problem.

How accurate are the results?

They use standard mathematical formulas and are accurate for the values you enter. Any rounding is for display only.

Will they work on my phone?

Yes. Every tool is responsive and works the same on phone, tablet, and desktop.

Which calculator should I start with?

Pick your topic: solving an equation, finding an area, working a triangle, or running statistics. Each tool links to related ones.

Do you store the numbers I enter?

No. Everything is calculated in your browser, and your inputs are not saved or sent anywhere.

Scroll to Top

The calculators and tools on Formula Factory are provided for general guidance and informational purposes only. Results are estimates based on standard formulas and the values you enter — they do not constitute professional engineering, electrical, or architectural advice. Always verify calculations with a qualified professional before making decisions for any safety-critical, code-compliance, or commercial application. Formula Factory makes no representations or warranties as to the accuracy or completeness of any result, and accepts no liability for errors, omissions, or any outcomes arising from reliance on this information.