QuantarizmQuantarizm
Calculators
Formula Library
Converters
Articles
QuantarizmQuantarizmMaking Numbers Meaningful.

Free math calculators, unit converters, and formula references — with clear steps.

Product

  • Calculators
  • Math
  • Financial
  • Formula Library
  • Converters
  • Articles

Company

  • About
  • Contact
Legal
  • Privacy Policy
  • Terms
  • Disclaimer
  • Cookies

© 2026 Quantarizm

Free tools · No account required

HomeCalculatorsConvertersFormula Library
  1. Home/
  2. Calculators/
  3. Math/
  4. Area Calculator

Area Calculator

Area of square, rectangle, triangle (Heron), trapezoid, circle, sector, ellipse, and parallelogram — with length units and square-unit conversions.

Geometry

  • Area Calculator
  • Circle Calculator
  • Triangle Calculator
  • Right Triangle Calculator
  • Pythagorean Theorem Calculator
  • Volume Calculator
  • Surface Area Calculator
  • Distance Calculator
  • Slope Calculator

How it works

Use one length unit for all sides. Area formulas: s², lw, Heron, ½(b₁+b₂)h, πr², sector fraction, πab, bh.

A=s² · A=lw · √[s(s−a)(s−b)(s−c)] · ½(b₁+b₂)h · πr² · (θ/360)πr² · πab · bh

When to use

Use this tool when you need to: land example: 220×99 ft → 21,780 ft² (½ acre). Square side 10. Triangle: three 77 ft sides (Heron). Sector: 60° of a 16 in pie.

How to use this tool

  1. Enter your values in the fields above.
  2. Review the formula and any mode options for your problem.
  3. Read the result and the step-by-step solution.

Land example: 220×99 ft → 21,780 ft² (½ acre). Square side 10. Triangle: three 77 ft sides (Heron). Sector: 60° of a 16 in pie.

Frequently asked questions

What is the Area Calculator?
Use one length unit for all sides. Area formulas: s², lw, Heron, ½(b₁+b₂)h, πr², sector fraction, πab, bh.
How do I use the Area Calculator?
Enter the required values, then calculate. The Area Calculator shows results, formulas, and step-by-step work when available. No account is required.
What formula does the Area Calculator use?
A=s² · A=lw · √[s(s−a)(s−b)(s−c)] · ½(b₁+b₂)h · πr² · (θ/360)πr² · πab · bh

You may also like

  • Circle CalculatorFrom any one of radius, diameter, circumference, or area, compute the other three measures of a circle.→
  • Triangle CalculatorSolve any triangle from three of sides a, b, c and angles A, B, C. Get area, medians, inradius, circumradius, and a scale diagram.→
  • Right Triangle CalculatorEnter any two of a, b, c, α, β, altitude h, area, or perimeter to solve a right triangle completely.→
  • Pythagorean Theorem CalculatorSolve a² + b² = c² given any two sides of a right triangle. See squares on each side and stepped solutions.→
  • Volume CalculatorVolume of sphere, cone, cube, cylinder, tank, capsule, cap, frustum, ellipsoid, pyramid, and tube with unit conversions.→
  • Surface Area CalculatorSurface area of sphere, cone, cube, cylinder, tank, capsule, cap, frustum, ellipsoid, and pyramid with unit conversions.→

Browse categories

  • General
  • Statistics

Other categories

  • General
  • Statistics
All math calculators→

Popular

  • Percentage Calculator
  • Average Calculator
  • Fraction Calculator
  • Triangle Calculator
All math calculators→

Area calculator

Evaluate the area of common plane shapes — square, rectangle, triangle (Heron), trapezoid, circle, sector, ellipse, and parallelogram. Enter all lengths in one unit; results include SI and common square-unit conversions (useful for land estimates).

Shape

22099

Complex regions can be split into these shapes and summed. All linear inputs must share the same unit. Sector angle is degrees or radians.

Try an example

How it works

What is area?

Area measures the extent of a two-dimensional figure in a plane — roughly how much paint covers a surface. It is the 2D counterpart of length (1D) and volume (3D). SI unit is the square meter (m²).

Eight common shapes

Square A=s². Rectangle A=l×w. Triangle via Heron √[s(s−a)(s−b)(s−c)] (or ½bh). Trapezoid ½(b₁+b₂)h. Circle πr². Sector (θ/360°)πr² or ½r²θ. Ellipse πab. Parallelogram b×h. Break complex figures into these and add.

Length and land units

Enter all edges in one unit (ft, m, …). Results convert to m², hectares, km², ft², yd², acres, and mi². Classic US example: 220×99 ft = 21,780 ft² = ½ acre.

More complex regions

Irregular parcels and composite figures are usually decomposed into rectangles, triangles, trapezoids, and circular pieces, then summed. Pair this tool with the circle or triangle calculators when you need other dimension combinations first.

Related geometry

Area and solid tools share common formulas with circle, triangle, and coordinate geometry calculators.

  • Circle Calculator
  • Triangle Calculator
  • Right Triangle Calculator
  • Pythagorean Theorem Calculator
  • Volume Calculator
  • Surface Area Calculator