Area Calculator

Find the area of 20 geometric shapes in seconds. Enter your measurements to get accurate results, useful formulas, perimeter calculations, and conversions to common area units.

Try a quick example

Select one to fill in the calculator

Choose a shape

Select the shape that matches the surface you want to measure.

Rectangle

Formula: A = l × w

Choose Measurement unit

Show area in

Enter Your Measurements

Enter each dimension in m. Use positive numbers only.

Length(m)

Width(m)

Choose Display options

Decimal places

Show calculation stepsShow unit conversionsShow perimeter when available

Material & cost estimate

Estimate the total area to cover, including extra material for cutting and waste.

Extra material allowance (%)

Cost per square meters (m²) (optional)

Base area32 m2

Extra area (0%)0 m2

Total area needed32 m2

Cost is an estimate in your chosen currency. Enter a price per area unit; currency symbols are intentionally not assumed.

How to use the area calculator

1
Choose a shape
Select the shape that matches the surface you are measuring, such as a rectangle, circle, triangle, or trapezoid.
2
Enter the measurements
Fill in the dimensions requested for that shape. Use the perpendicular height where a formula calls for height.
3
Select your units
Choose the unit used for your measurements and the area unit you want in your final result.
4
Review your answer
Read the area, formula, and calculation steps. Convert the result into other units or export it as a CSV file.
5
Estimate project materials
If you are planning flooring, tiles, or paint coverage, add a waste allowance and optionally enter a price per unit of area.

Area formulas at a glance

Area measures the amount of two-dimensional surface enclosed by a shape. Each formula uses the dimensions relevant to that shape.

Shape	Area formula
Square	A = s²
Rectangle	A = l × w
Triangle	A = ½ × b × h
Circle	A = π × r²
Ellipse	A = π × a × b
Trapezoid	A = ½ × (a + b) × h
Parallelogram	A = b × h
Rhombus / kite	A = ½ × d₁ × d₂
Circle sector	A = (θ / 360) × π × r²
Circular ring	A = π × (R² − r²)
Regular polygon	A = n × s² / [4 tan(π/n)]

Here, A is area, s is side length, l is length, w is width, b is base, h is perpendicular height, r is radius, θ is the central angle in degrees, and n is the number of polygon sides.

Helpful measurement tips

Use perpendicular height

For triangles and parallelograms, height means the shortest perpendicular distance to the base, not the sloping side.

Keep units consistent

Enter all measurements using the selected length unit. The calculator converts the squared result into your chosen area unit.

Measure irregular spaces carefully

For an L-shaped room or uneven plot, divide the space into smaller rectangles and triangles, calculate each part, and add the areas together. Subtract any cut-outs.

Plan for material waste

Flooring, tiles, and other materials may need extra coverage for trimming, breakage, and awkward corners. The waste allowance helps estimate that additional amount.

Understand the perimeter

Area measures the space inside a shape, while perimeter measures the distance around its boundary. Some shapes require additional side lengths to calculate perimeter.

Check your measurements

Small measurement errors can affect the final result, particularly for large surfaces. For legal land boundaries or construction-critical measurements, use appropriate professional surveying methods.

Frequently asked questions

What is the formula for calculating area?+

The formula depends on the shape. A rectangle uses length multiplied by width, a triangle uses half the base multiplied by its perpendicular height, and a circle uses π multiplied by the square of its radius.

Can I calculate area in square feet or acres?+

Yes. Enter your measurements in a supported length unit and select square feet, square yards, acres, hectares, square meters, or another supported area unit for the result.

What is the difference between area and perimeter?+

Area measures the amount of surface inside a two-dimensional boundary and is expressed in square units. Perimeter measures the total length around the boundary and is expressed in regular length units.

How do I calculate the area of an irregular shape?+

Break the shape into smaller, measurable shapes such as rectangles and triangles. Calculate each area separately, add the areas together, and subtract any sections that are not part of the surface.

Can I use this calculator for flooring or painting?+

Yes. Calculate the surface area, then use the material allowance to estimate extra coverage. For paint, compare the resulting area with the coverage stated on the paint container. For flooring, account for cuts, waste, and the manufacturer's recommendations.

Are the calculations sent to a server?+

No. The geometry calculations run in your browser. The calculator does not need an account or an external calculation API. Your calculation history remains in the current page session and is cleared when you reset or clear it.

Area Calculator

Find the area of 20 geometric shapes in seconds. Enter your measurements to get accurate results, useful formulas, perimeter calculations, and conversions to common area units.

Try a quick example

Select one to fill in the calculator

Choose a shape

Select the shape that matches the surface you want to measure.

Rectangle

Formula: A = l × w

Choose Measurement unit

Show area in

Enter Your Measurements

Enter each dimension in m. Use positive numbers only.

Length(m)

Width(m)

Choose Display options

Decimal places

Show calculation stepsShow unit conversionsShow perimeter when available

Material & cost estimate

Estimate the total area to cover, including extra material for cutting and waste.

Extra material allowance (%)

Cost per square meters (m²) (optional)

Base area32 m2

Extra area (0%)0 m2

Total area needed32 m2

Cost is an estimate in your chosen currency. Enter a price per area unit; currency symbols are intentionally not assumed.

How to use the area calculator

1
Choose a shape
Select the shape that matches the surface you are measuring, such as a rectangle, circle, triangle, or trapezoid.
2
Enter the measurements
Fill in the dimensions requested for that shape. Use the perpendicular height where a formula calls for height.
3
Select your units
Choose the unit used for your measurements and the area unit you want in your final result.
4
Review your answer
Read the area, formula, and calculation steps. Convert the result into other units or export it as a CSV file.
5
Estimate project materials
If you are planning flooring, tiles, or paint coverage, add a waste allowance and optionally enter a price per unit of area.

Area formulas at a glance

Area measures the amount of two-dimensional surface enclosed by a shape. Each formula uses the dimensions relevant to that shape.

Shape	Area formula
Square	A = s²
Rectangle	A = l × w
Triangle	A = ½ × b × h
Circle	A = π × r²
Ellipse	A = π × a × b
Trapezoid	A = ½ × (a + b) × h
Parallelogram	A = b × h
Rhombus / kite	A = ½ × d₁ × d₂
Circle sector	A = (θ / 360) × π × r²
Circular ring	A = π × (R² − r²)
Regular polygon	A = n × s² / [4 tan(π/n)]

Here, A is area, s is side length, l is length, w is width, b is base, h is perpendicular height, r is radius, θ is the central angle in degrees, and n is the number of polygon sides.

Helpful measurement tips

Use perpendicular height

For triangles and parallelograms, height means the shortest perpendicular distance to the base, not the sloping side.

Keep units consistent

Enter all measurements using the selected length unit. The calculator converts the squared result into your chosen area unit.

Measure irregular spaces carefully

For an L-shaped room or uneven plot, divide the space into smaller rectangles and triangles, calculate each part, and add the areas together. Subtract any cut-outs.

Plan for material waste

Flooring, tiles, and other materials may need extra coverage for trimming, breakage, and awkward corners. The waste allowance helps estimate that additional amount.

Understand the perimeter

Area measures the space inside a shape, while perimeter measures the distance around its boundary. Some shapes require additional side lengths to calculate perimeter.

Check your measurements

Small measurement errors can affect the final result, particularly for large surfaces. For legal land boundaries or construction-critical measurements, use appropriate professional surveying methods.

Frequently asked questions

What is the formula for calculating area?+

Can I calculate area in square feet or acres?+

Yes. Enter your measurements in a supported length unit and select square feet, square yards, acres, hectares, square meters, or another supported area unit for the result.

What is the difference between area and perimeter?+

How do I calculate the area of an irregular shape?+

Break the shape into smaller, measurable shapes such as rectangles and triangles. Calculate each area separately, add the areas together, and subtract any sections that are not part of the surface.

Can I use this calculator for flooring or painting?+

Are the calculations sent to a server?+

Try a quick example

Choose a shape

Rectangle

Enter Your Measurements

Choose Display options

Material & cost estimate

How to use the area calculator

Choose a shape

Enter the measurements

Select your units

Review your answer

Estimate project materials

Area formulas at a glance

Helpful measurement tips

Use perpendicular height

Keep units consistent

Measure irregular spaces carefully

Plan for material waste

Understand the perimeter

Check your measurements

Frequently asked questions

Try a quick example

Choose a shape

Rectangle

Enter Your Measurements

Choose Display options

Material & cost estimate

How to use the area calculator

Choose a shape

Enter the measurements

Select your units

Review your answer

Estimate project materials

Area formulas at a glance

Helpful measurement tips

Use perpendicular height

Keep units consistent

Measure irregular spaces carefully

Plan for material waste

Understand the perimeter

Check your measurements

Frequently asked questions