All Free Developer Tools

Calculate chemical concentrations

Calculate density from mass and volume

Calculate solution dilutions

Calculate gas properties using gas laws

Calculate remaining amount, time, or half-life for exponential decay

Calculate molality of solutions

Calculate molarity of solutions

Calculate molecular weight of compounds

Calculate pH from concentration

Calculate chemical reaction stoichiometry

Calculate acceleration from velocity and time

Calculate force using Newton's laws

Calculate kinetic energy from mass and velocity

Calculate potential energy

Calculate electrical and mechanical power

Calculate pressure from force and area

Calculate velocity from distance and time

Calculate area of squares, rectangles, triangles, circles, and more

Calculate mean, median, mode, and range from a list of numbers

Add, subtract, multiply, and divide with a free online calculator

Add, subtract, multiply, and divide integers too large for a standard calculator

Add, subtract, and convert binary numbers to decimal and hex

Find radius, diameter, circumference, area, arc length, and sector area

Find GCD, HCF, LCM, and all common factors of two or more numbers

Compute a confidence interval for a mean or a proportion

Find the distance between two points in 2D or 3D

Calculate powers, roots, and a^b with a step-by-step exponent

List all factors and factor pairs of a whole number

Add, subtract, multiply, and divide fractions and mixed numbers

Find the GCF, GCD, or HCF of two or more whole numbers

Add, subtract, and convert hexadecimal numbers to decimal and binary

Find the LCM of two or more whole numbers

Calculate logarithms in any base, including ln, log10, and log2

Divide with a remainder and see every long-division step

Add, multiply, transpose, and invert 2×2 and 3×3 matrices

Find mean, median, mode, and range from a list of numbers

Find the nth term and sum of arithmetic or geometric sequences

Find a p-value from a z-score, t-statistic, or chi-square statistic

Calculate percent error between experimental and accepted values

Find X% of Y, reverse percentages, and percentage change

Calculate nPr permutations and nCr combinations

Break a whole number into its prime factors

Calculate AND, OR, complement, and binomial probabilities

Solve a² + b² = c² for a missing side of a right triangle

Solve ax² + bx + c = 0 and see discriminant, roots, and vertex

Generate random integers or decimals in a range, in your browser

Simplify ratios, find a missing term, or split a total by ratio

Solve a right triangle for sides and angles with SOHCAHTOA

Calculate square roots, cube roots, and nth roots

Round a number to decimal places, significant figures, or a place value

Estimate survey sample size from confidence level and margin of error

Trig, logs, exponents, and parentheses in a free online scientific calculator

Convert numbers to and from scientific notation (a × 10^n)

Find slope, intercept, distance, and line equation from two points

Calculate sample or population standard deviation and variance

Descriptive statistics: mean, median, quartiles, variance, and SD

Calculate surface area of cubes, spheres, cylinders, and prisms

Solve a triangle from SSS, SAS, ASA, AAS, or SSA and find area

Calculate volume of cubes, spheres, cylinders, cones, and more

Convert a value to a z-score, percentile, or raw score

Convert between length units

Convert between mass/weight units

Convert between temperature scales

Convert between area units

Convert between volume units

Convert between speed/velocity units

Convert between energy units

Convert between power units

Convert between pressure units

Convert between force units

Convert between frequency units

Convert between fuel efficiency units

Convert between density units

Convert between electrical current units

Convert between astronomical units

Convert between weight units

Convert between angle units

Convert between time units

Convert between digital storage units

Convert between Unix timestamps and human-readable dates

Estimate body fat with the DoD/Army circumference method used in AR 600-9

Educational Widmark blood-alcohol estimate. Not for deciding whether to drive

Calculate body mass index from height and weight with WHO adult categories

Estimate basal metabolic rate with Mifflin–St Jeor, Harris–Benedict, or Katch–McArdle

Estimate body-fat percentage from Navy/Hodgdon–Beckett circumference measurements

Estimate BSA with Mosteller and Du Bois formulas from height and weight

Estimate daily calorie needs (TDEE) from BMR and activity level

Estimate pregnancy due date from last menstrual period using Naegele’s rule

Find the adult weight range that corresponds to BMI 18.5–24.9 for a given height

Compare Devine, Robinson, Miller, and Hamwi ideal-body-weight formulas

Estimate lean body mass with Boer, James, and Hume equations

Check adult BMI against the WHO overweight and obesity cutoffs

Check adult BMI against WHO underweight and thinness categories. Not an eating-disorder diagnosis

Estimate exercise calorie burn from MET, body weight, and duration

Plan daily carbohydrate grams from calorie needs and carb percentage or g/kg

Estimate daily fat grams from calorie needs and a 20–35% fat target

Split daily calories into protein, carbohydrate, and fat grams

Estimate 1RM from a submaximal set with Epley and Brzycki formulas

Solve running pace, finish time, or distance from the other two values

Estimate daily protein grams from body weight and activity goal

Find training heart-rate zones with 220−age and the Karvonen method

Unofficial legacy Points estimate from calories, fat, and fiber. Not affiliated with WW