86 free math calculators covering percentages, algebra, geometry, volumes, trigonometry, vectors, matrices, and coordinate geometry. Every tool shows the formula, a worked example, and step-by-step results.
Evaluate |x| and solve absolute-value equations and inequalities with steps.
Add, subtract, multiply, and divide with safe division-by-zero handling.
Roots, powers, trigonometry, logarithms, exponentials, absolute value, and factorials.
Raise any base to any power, including negative and fractional exponents, with rules explained.
Principal square root of any non-negative number, with perfect-square table.
Real cube root of any number — negatives included.
Any-degree root with correct handling of negative radicands.
n! for whole numbers 0–170 with readable thousands separators.
Remainders with floor-based modulo (sign follows the divisor).
Add, subtract, multiply, and divide fractions with auto-reduction to lowest terms.
Decimals to lowest-terms fractions with adjustable max denominator.
Any fraction to its decimal equivalent at six-decimal precision.
Natural, common, or any custom-base logarithm via the change-of-base formula, with steps.
Antilog: raise e, 10, or any base to your power.
Find p% of x, percentage change, and reverse percentages with full steps.
Calculate percentage increase between an old and a new value.
Calculate percentage decrease between an old and a new value.
Directional increase or decrease between an old and a new value, with the trap cases explained.
Symmetric difference using the average as the base.
Simplify ratios with GCD or solve A:B = C:D proportions.
Real or complex roots of ax² + bx + c = 0 with the discriminant shown every time.
Linear equations, quadratics, and 2×2 systems with working shown.
Unordered selections nCr with the factorial formula shown.
Ordered arrangements nPr with the factorial formula shown.
Up to five value–weight pairs with heavier weights pulling more.
Area from radius with a ready reference table for radii 1–10 and diameter guidance.
Distance around a circle from its radius, plus a 1–10 table.
Base×height, Heron's formula, or vertex coordinates (shoelace) — pick the tab matching your data.
All three interior angles from three side lengths (SSS).
Hypotenuse from two legs, or a missing leg from hypotenuse + leg — both directions with steps.
Direct hypotenuse length from the two legs, step by step.
Missing side from one side + two angles (law of sines).
Third side from two sides + included angle (law of cosines).
V = s³ — enter dimensions, get the result with steps.
V = l × w × h — enter dimensions, get the result with steps.
V = (½ × b × h) × L — enter dimensions, get the result with steps.
V = B × h — enter dimensions, get the result with steps.
V = (s² × h) / 3 — enter dimensions, get the result with steps.
V = πr²h — enter dimensions, get the result with steps.
V = πr²h / 3 — enter dimensions, get the result with steps.
V = (4/3)πr³ — enter dimensions, get the result with steps.
V = (2/3)πr³ — enter dimensions, get the result with steps.
V = (4/3)πabc — enter dimensions, get the result with steps.
V = 2π²Rr² — enter dimensions, get the result with steps.
SA = 2(lw + lh + wh) — enter dimensions, get the result with steps.
Cylinder: 2πrh · Cone: πrl, l = √(r² + h²) — enter dimensions, get the result with steps.
Area, perimeter, volume, and surface area for seven shapes instantly.
sin(θ) = opposite / hypotenuse — enter degrees or radians, undefined cases flagged.
cos(θ) = adjacent / hypotenuse — enter degrees or radians, undefined cases flagged.
tan(θ) = sin(θ) / cos(θ) — enter degrees or radians, undefined cases flagged.
sec(θ) = 1 / cos(θ) — enter degrees or radians, undefined cases flagged.
csc(θ) = 1 / sin(θ) — enter degrees or radians, undefined cases flagged.
cot(θ) = 1 / tan(θ) = cos(θ) / sin(θ) — enter degrees or radians, undefined cases flagged.
cos, sin, and tan of any angle from the unit circle.
All solutions of sin/cos/tan(x) = k in [0°, 360°).
Straight-line distance in 2D or 3D with step-by-step working.
2D/3D coordinates or great-circle lat/lon distance.
Pythagorean straight-line distance between two 2D points.
Grid distance |dx| + |dy| for navigation and robotics.
Exact middle of two points by averaging coordinates.
Rise over run through two points; vertical lines honestly flagged undefined.
y = mx + b from two points or from slope + point.
Line through a new point with the original slope kept.
Negative-reciprocal slope through your point; verticals handled.
Where a line through two points crosses the x-axis.
Where a line through two points crosses the y-axis.
Exact crossing from slope-intercept or point-pair inputs.
Crossing angle from slopes or direction vectors; perpendiculars at 90°.
Both directions, degrees or radians, with worked examples.
2D/3D vector angle from dot product and magnitudes, fully worked.
Component-wise resultant of two 2D/3D vectors.
3D perpendicular vector with the basis-vector reference.
Scalar alignment measure of two 2D/3D vectors, worked.
Length of a 2D/3D vector via the Pythagorean formula.
2×2/3×3 entry-wise sums with every cell worked.
2×2/3×3 entry-wise differences with every cell worked.
Row-times-column 2×2/3×3 products with each entry worked.
2×2/3×3 determinant via cofactor expansion; singularity revealed.
Adjugate/determinant inverse; singular matrices flagged.
2×2/3×3 systems via determinant replacement.
Row-reduction with partial pivoting; every step shown.
Round up to the nearest integer — negatives handled correctly.
Round down to the nearest integer — negatives handled correctly.
Evaluate linear, quadratic, cubic, exponential, sine, log at any x.
Size a first-order CSTR from flow, conversion, and rate constant.
Generate unbiased random numbers, dice rolls, and random list picks.
For school homework, the most-used tools are the Percentage Calculator, Fraction Calculator, Square Root Calculator, Pythagorean Theorem Calculator, and Quadratic Equation Calculator. Each page shows the formula, a worked example, and step-by-step results, so you can check your own working, not just copy an answer.