Mathematics calculators
GCD, circle area, percent, volumes and sequences. Each calculator keeps its own formula on its own page.
Geometry
Annulus area calculator
Annulus area: the outer radius R and the inner radius r.
Use calculator →Arc length calculator
Arc length: an angle in degrees and a radius.
Use calculator →Arccos calculator
Arccos (inverse cosine) calculator: x from −1 to 1 and pick degrees or radians.
Use calculator →Arcsin calculator
Arcsin (inverse sine): an x from −1 to 1.
Use calculator →Arctan calculator
Arctan (inverse tangent): an x, any number.
Use calculator →Circumference calculator
Circumference calculator: the radius, not the diameter.
Use calculator →Circle sector area
Circle sector area: an angle in degrees and a radius.
Use calculator →Circle segment calculator
At r = 2 and 90° the area is 1.14, the chord 2.83, the sagitta 0.59.
Use calculator →Cotangent calculator
Cotangent: an angle in degrees.
Use calculator →Cylinder volume (from base circumference)
Cylinder volume (from base circumference): the base circumference and the height.
Use calculator →Distance from point to line
Distance from point to line: A, B, C of the line Ax+By+C=0 and the point x, y.
Use calculator →Equilateral triangle area calculator
Equilateral triangle area calculator: side length a.
Use calculator →Equilateral triangle height calculator
Equilateral triangle height: side a.
Use calculator →Law of cosines calculator
Law of cosines (side c): sides a and b and the angle γ between them, in degrees.
Use calculator →Law of sines calculator
Law of sines (ratio): side a and the angles α and β in degrees.
Use calculator →Number of polygon diagonals
Number of polygon diagonals: the number of vertices n.
Use calculator →Parallelogram area (with sine)
Parallelogram area (with sine): sides a, b and the angle in degrees.
Use calculator →Sum of angles in a triangle
Sum of angles in a triangle: two angles in degrees.
Use calculator →Sum of polygon angles
Sum of polygon angles: the number of sides n.
Use calculator →Algebra
Decimal to fraction calculator
Decimal to fraction: 0.75 is 3/4. 0.2 is 1/5.
Use calculator →Fraction Calculator
Fraction calculator: 1/2 + 1/3 is 5/6. 3/4 × 2/5 is 3/10.
Use calculator →Absolute value calculator
Absolute value calculator: a number, plus or minus.
Use calculator →Ceiling calculator
Ceiling (round up): an x.
Use calculator →Log calculator
Common logarithm: an x greater than zero.
Use calculator →Difference of squares calculator
Difference of squares: a and b.
Use calculator →Exponential function eˣ calculator
Exponential function eˣ calculator: the exponent x.
Use calculator →Floor calculator
Floor (integer part): an x.
Use calculator →Fractional part calculator
Fractional part calculator: a number.
Use calculator →Fractional power
Fractional power: x, numerator m and denominator n.
Use calculator →Cosh calculator
Hyperbolic cosine (cosh): x.
Use calculator →Sinh calculator
Hyperbolic sine (sinh): x.
Use calculator →Tanh calculator
Hyperbolic tangent (tanh): x.
Use calculator →Linear function value
Linear function value: slope a, intercept b and the argument x.
Use calculator →Linear interpolation calculator
Linear interpolation: (x₁, y₁), (x₂, y₂) and x.
Use calculator →Logarithm to any base
Logarithm to any base: base a and the number x.
Use calculator →Maximum of two numbers
Maximum of two numbers: a and b.
Use calculator →Minimum and maximum of numbers
Minimum and maximum of numbers: a, b and optional c.
Use calculator →Natural logarithm
Natural logarithm: an x greater than zero.
Use calculator →Nth root calculator
nth root: x and the degree n.
Use calculator →Percentage change calculator
Percentage change calculator: the old value and the new value.
Use calculator →Ratio of two numbers calculator
Ratio of two numbers calculator: two integers.
Use calculator →Round to n decimal places
Round to n decimal places: x and k places.
Use calculator →Scale (length conversion)
Scale (length conversion): the length on the map and the scale.
Use calculator →Sign of a number (signum)
Sign of a number (signum): an x.
Use calculator →Square of a sum
Square of a sum: a and b.
Use calculator →Statistics
Attendance Calculator
Attendance: 85 present out of 100 classes is 85%. Shows how many more you can miss at the chosen threshold.
Use calculator →Geometric mean
Geometric mean: two numbers.
Use calculator →Harmonic mean calculator
Harmonic mean: a and b.
Use calculator →Median (5 numbers)
Median (5 numbers): five numbers in five fields.
Use calculator →Permutation calculator
Permutation calculator: n.
Use calculator →Range (max − min)
Range (max − min): intended: max − min of a comma list; actual: a number read, then range of one number = 0.
Use calculator →Standard deviation (3 numbers)
Standard deviation (3 numbers): three numbers.
Use calculator →Variance calculator
Variance (n numbers): a list of numbers, comma, space or semicolon.
Use calculator →Other
Roman Numeral Converter
Roman numeral converter: 2026 is MMXXVI. 14 is XIV. Range 1 to 3999.
Use calculator →GPA Calculator
GPA calculator: A and B at 3 credits each give 3.50. A at 4 and C at 2 give 3.33.
Use calculator →ECTS Weighted Average Calculator
ECTS weighted average: grades 5 and 3 with 6 ECTS each give 4.00.
Use calculator →Random Number Generator
Random number generator: inclusive integers from minimum to maximum. Optional no repeats.
Use calculator →Arithmetic mean calculator
Arithmetic mean calculator: a list of numbers in one field, with spaces or commas.
Use calculator →Arithmetic sequence term
Arithmetic sequence term: the first term a₁, the common difference r and the index n.
Use calculator →Arithmetic series sum calculator
Pick whether you know the ends of the list or the step.
Use calculator →Circle area calculator
Circle area calculator: the radius.
Use calculator →Combinations calculator
Combinations C(n,k): n and k.
Use calculator →Cone volume calculator
Cone volume calculator: V = (1/3) × π × r² × h.
Use calculator →Cosine of an angle calculator
Pick from an angle or from triangle sides.
Use calculator →Cube volume calculator
All twelve edges are equal, so one number is enough.
Use calculator →Cylinder lateral area calculator
Cylinder lateral area calculator: Alateral = 2 × π × r × h.
Use calculator →Cylinder volume calculator
You get how much a can, a pipe, or a homework cylinder holds.
Use calculator →Distance between two points calculator
Distance between two points: x₁, y₁, x₂, y₂.
Use calculator →Divide an amount in a ratio calculator
Divide an amount in a ratio calculator: the whole and two ratio parts.
Use calculator →Ellipse area calculator
Ellipse area calculator: both semi-axes.
Use calculator →Factorial calculator
Factorial calculator: a natural number n.
Use calculator →GCD calculator
GCD calculator: two integers.
Use calculator →Geometric sequence term
Geometric sequence term: the first term a₁, the ratio q and the index n.
Use calculator →Geometric series sum calculator
Geometric series sum calculator: the first term, the ratio, and the term count.
Use calculator →LCM calculator
LCM calculator: two integers.
Use calculator →Linear equation calculator
Linear equation: coefficient a and constant term b of ax + b = 0.
Use calculator →Logarithm calculator
Logarithm calculator: the base and the number.
Use calculator →Median calculator
Median calculator: a list of numbers.
Use calculator →Midpoint of segment
Midpoint of segment: x₁, y₁, x₂, y₂.
Use calculator →Modulo calculator
Modulo (remainder): dividend a and divisor b, both non-negative.
Use calculator →Parallelogram area calculator
Parallelogram area calculator: the base and the height perpendicular to it.
Use calculator →Percentage change calculator
Percentage change: the new value and the old value.
Use calculator →Percentage calculator
Percentage calculator: a number and a percent without the % sign.
Use calculator →Power / exponent calculator
Power / exponent calculator: a base and an exponent.
Use calculator →Prism volume calculator
Prism volume calculator: a ready base area and the height between the bases.
Use calculator →Pyramid volume calculator
Pyramid volume calculator: V = (1/3) × base area × h.
Use calculator →Pythagorean theorem calculator
Pick which side you need and type the two you know.
Use calculator →Quadratic equation calculator
Quadratic equation: coefficients a, b and c of ax² + bx + c = 0.
Use calculator →Rectangle area calculator
You get the floor, the frame, or the homework rectangle in cm² or in².
Use calculator →Rhombus area calculator
Rhombus area calculator: both diagonals.
Use calculator →Rule of three calculator
Rule of three calculator: a known pair and a third number.
Use calculator →Sine of an angle calculator
Pick from an angle or from triangle sides (sine angle).
Use calculator →Sphere surface area calculator
You get the skin, four circle areas at the same r, not the water inside.
Use calculator →Sphere volume calculator
Sphere volume calculator: V = (4/3) × π × r³.
Use calculator →Square root calculator
Square root calculator: a non-negative number.
Use calculator →Standard deviation calculator
Standard deviation: two numbers.
Use calculator →Degrees to radians
Degrees to radians: an angle in degrees.
Use calculator →Tangent of an angle calculator
Tangent of an angle: an angle in degrees.
Use calculator →Trapezoid area calculator
Trapezoid area calculator: the two parallel bases and the height between them.
Use calculator →Triangle area calculator
Triangle area calculator: the base and the height perpendicular to it.
Use calculator →Heron's formula calculator
Triangle area (Heron): three sides in centimetres.
Use calculator →nPr calculator
Variations V(n,k): n and k.
Use calculator →Vector length calculator
Vector length calculator: x and y.
Use calculator →Weighted average calculator
Weighted average: a value and a weight.
Use calculator →Grade calculator
Grade calculator: percent = earned / maximum × 100.
Use calculator →Articles
Short guides for the formulas in this category. Each article leads to a calculator.