Free Online Calculators & Converters
Calculate percentages, convert units, estimate loan payments, and more with our free online math tools. Instant results with no signup required.
Percentage Calculator
Solve any percentage problem instantly. Calculate what X% of Y is, find percentage increase or decrease, or determine what percent one number is of another.
Use tool βAge Calculator
Enter your date of birth to see your exact age in years, months, and days. Also see days until your next birthday and the day of the week you were born.
Use tool βBMI Calculator
Enter your height and weight to calculate your Body Mass Index (BMI) and see where you fall on the standard BMI scale. Supports both metric and imperial units.
Use tool βLoan Payment Calculator
Estimate your monthly loan payment based on principal amount, interest rate, and loan term. See total interest paid and the full repayment breakdown.
Use tool βCompound Interest Calculator
See how your savings or investments grow over time with compound interest. Adjust principal, rate, compounding frequency, and contributions to plan your financial future.
Use tool βTip Calculator
Calculate the right tip amount and split the bill evenly among any number of people. Choose from common tip percentages or enter a custom amount.
Use tool βUnit Converter
Convert between units of length, weight, temperature, volume, speed, area, and more. A universal converter for everyday and professional use.
Use tool βLength Converter
Convert between all common length units instantly. Supports meters, feet, inches, centimeters, millimeters, kilometers, miles, yards, and more.
Use tool βWeight Converter
Convert between kilograms, pounds, ounces, grams, milligrams, metric tons, and more. Instant, accurate weight conversions.
Use tool βTemperature Converter
Convert temperatures between Celsius, Fahrenheit, and Kelvin with a single input. See the conversion formulas and common reference points.
Use tool βCircle Area Calculator
Enter the radius of any circle and instantly compute its area using the standard ΟrΒ² formula. Ideal for geometry homework, engineering, and design projects.
Use tool βCircle Circumference Calculator
Quickly determine the circumference of a circle by providing the radius. Uses the precise 2Οr formula for accurate perimeter measurement.
Use tool βTriangle Area Calculator
Compute the area of any triangle by entering the base and height. Uses the standard Β½ Γ base Γ height formula for fast, accurate results.
Use tool βRectangle Area Calculator
Find the area of any rectangle by entering its length and width. Perfect for calculating room sizes, material quantities, and garden plots.
Use tool βRectangle Perimeter Calculator
Enter the length and width to find the total perimeter of a rectangle. Great for planning fences, picture frames, and border materials.
Use tool βSphere Volume Calculator
Determine the volume of any sphere by entering the radius. Uses the standard (4/3)ΟrΒ³ formula for tanks, balls, and spherical containers.
Use tool βSphere Surface Area Calculator
Calculate how much surface a sphere has by entering its radius. The 4ΟrΒ² formula helps estimate material for coating, wrapping, or painting spherical objects.
Use tool βCylinder Volume Calculator
Enter the radius and height of a cylinder to compute its volume. Uses ΟrΒ²h β useful for sizing tanks, cans, pipes, and cylindrical containers.
Use tool βCone Volume Calculator
Find the volume of any cone by entering its base radius and height. The (1/3)ΟrΒ²h formula gives you the exact capacity for funnels, cones, and more.
Use tool βTrapezoid Area Calculator
Compute the area of a trapezoid by entering both parallel sides and the height. Applies the standard Β½(a + b) Γ h formula for quick results.
Use tool βParallelogram Area Calculator
Enter the base and perpendicular height to calculate the area of any parallelogram. Simple, fast, and accurate for all parallelogram shapes.
Use tool βEllipse Area Calculator
Enter the semi-major and semi-minor axes to compute the area of an ellipse using Ο Γ a Γ b. Useful for oval designs, tracks, and engineering.
Use tool βCube Volume Calculator
Find the volume of a cube by entering the side length. Computes sΒ³ instantly β ideal for packaging, storage, and cubic capacity planning.
Use tool βPythagorean Theorem Calculator
Enter two sides of a right triangle to find the hypotenuse using aΒ² + bΒ² = cΒ². Essential for construction, navigation, and geometry problems.
Use tool βDiagonal Calculator
Find the diagonal of any rectangle by entering its length and width. Applies β(lΒ² + wΒ²) for screen sizes, room diagonals, and construction layouts.
Use tool βGCD Calculator
Enter two numbers to find their greatest common divisor (GCD), also known as the highest common factor (HCF). Essential for simplifying fractions.
Use tool βLCM Calculator
Enter two numbers to find their least common multiple (LCM). Useful for adding fractions with different denominators and solving scheduling problems.
Use tool βFactorial Calculator
Enter a non-negative integer to calculate its factorial (n!). Handles values up to 170 for combinatorics, probability, and permutation problems.
Use tool βFibonacci Calculator
Enter a position to get the corresponding Fibonacci number. The Fibonacci sequence appears in nature, art, algorithms, and financial analysis.
Use tool βPrime Number Checker
Enter a number to determine whether it is prime. Also displays the nearest prime numbers above and below your input for quick reference.
Use tool βSquare Root Calculator
Enter a number to compute its square root. Supports decimals and provides high-precision results for math, science, and engineering work.
Use tool βCube Root Calculator
Enter any number to find its cube root. Unlike square roots, cube roots work with negative numbers too β perfect for algebra and volume problems.
Use tool βExponent Calculator
Raise any base to any power β including decimals, fractions, and negative exponents. A versatile tool for algebra, physics, and financial formulas.
Use tool βLogarithm Calculator
Compute logarithms for any positive number with any base. Defaults to base 10 but supports natural log (e), base 2, and any custom base.
Use tool βModulo Calculator
Compute the remainder when dividing one number by another. The modulo operation is fundamental in programming, cryptography, and clock arithmetic.
Use tool βAverage Calculator
Enter a list of comma-separated numbers to compute their arithmetic mean. Works with any count of values β from two to thousands.
Use tool βQuadratic Equation Solver
Enter coefficients a, b, and c to solve axΒ² + bx + c = 0. Displays both roots, the discriminant, and whether roots are real or complex.
Use tool βRatio Calculator
Solve proportions by entering three known values to find the fourth. If A:B = C:D, enter A, B, and C to calculate D automatically.
Use tool βScientific Notation Converter
Convert any number into scientific notation or back to standard form. Handles extremely large and small values for science and engineering.
Use tool βCombination Calculator
Find how many ways you can choose r items from n items when order does not matter. Uses the nCr = n! / (r!(n-r)!) formula.
Use tool βPermutation Calculator
Determine how many ways you can arrange r items from n items when order matters. Uses nPr = n! / (n-r)! for rankings and seating charts.
Use tool βElectricity Cost Calculator
Estimate the cost of running an electrical device based on its wattage, usage hours, and your electricity rate.
Use tool βOhm's Law Calculator
Enter any two of voltage (V), current (I), and resistance (R) to calculate the third using Ohm's Law.
Use tool βPercentage Increase Calculator
Enter an original value and a new value to calculate the percentage increase between them.
Use tool βPercentage Decrease Calculator
Enter an original value and a new value to calculate the percentage decrease between them.
Use tool βMean Calculator
Enter a list of numbers to calculate the arithmetic mean. Supports any number of values.
Use tool βMedian Calculator
Enter numbers to find the median β the middle value when sorted. For even counts, it's the average of the two middle values.
Use tool βStandard Deviation Calculator
Enter numbers to calculate the standard deviation, which measures how spread out the values are from the mean.
Use tool βFuel Cost Calculator
Estimate the fuel cost of a trip by entering the distance, your vehicle's fuel economy, and the price per gallon/liter.
Use tool βPaint Calculator
Enter room dimensions to estimate how many gallons of paint you need. Accounts for doors and windows.
Use tool βConcrete Calculator
Calculate the volume of concrete needed for slabs, footings, and columns based on dimensions.
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