Calculate Area
Select a shape and enter its dimensions to calculate the area instantly.
Rectangle / Square
📐 Room Floor Area
A room 4m × 5m
🖼️ Picture Frame
A frame 8in × 10in
🏡 Garden Bed
A bed 3ft × 6ft
Triangle
🔺 Sail Area
A sail 3m base × 5m height
🏔️ Gable End
Gable 20ft wide × 8ft tall
🎨 Canvas Section
Triangle 12in × 9in
Circle
Don't know the radius? Radius = diameter ÷ 2
🍕 Pizza Size
12-inch pizza (radius 6in)
🏊 Round Pool
Pool with 4m radius
⭕ Circular Garden
Garden with 5ft radius
Trapezoid
🏠 Roof Section
Trapezoid: 4m, 6m bases, 3m height
🛤️ Land Plot
Plot: 50ft, 80ft sides, 40ft deep
Parallelogram
🧱 Tile Pattern
Parallelogram tile 15cm × 10cm
📦 Box Side
Slanted panel 2ft base × 1.5ft height
Ellipse (Oval)
🏈 Oval Track
Track 100m × 60m (semi-axes 50m × 30m)
🥚 Elliptical Table
Table 6ft × 4ft (semi-axes 3ft × 2ft)
Regular Polygon
⬡ Hexagonal Tile
Hexagon (6 sides) with 10cm sides
⬠ Pentagon Paver
Pentagon (5 sides) with 8in sides
Octagon (8 sides) with 12in sides
How to Calculate Area
Area is the measurement of a two-dimensional surface, expressed in square units. Whether you're measuring a room for flooring, calculating paint coverage, or sizing a garden bed, understanding area calculations is essential.
Key Formulas
| Shape | Formula | Variables |
|---|---|---|
| Rectangle | A = w × h | width, height |
| Triangle | A = ½ × b × h | base, height |
| Circle | A = π × r² | radius |
| Trapezoid | A = ½ × (a + b) × h | parallel sides, height |
| Parallelogram | A = b × h | base, height |
| Ellipse | A = π × a × b | semi-major, semi-minor axes |
Tips for Accurate Measurements
- Use the same units — Don't mix meters with feet in the same calculation.
- Measure twice — Small errors multiply when calculating area.
- For irregular shapes — Break them into simpler shapes, calculate each, then add together.
- Height means perpendicular — For triangles and trapezoids, height is the straight vertical distance, not a slanted side.
Frequently Asked Questions
What is area?
How do I calculate the area of a rectangle?
How do I calculate the area of a triangle?
How do I calculate the area of a circle?
What is the difference between area and perimeter?
How do I convert between square feet and square meters?
How do I calculate the area of an irregular shape?
What is the area of a square?
How do I find the area of a trapezoid?
Why is π (pi) used in circle area calculations?
Privacy & Limitations
- All calculations run entirely in your browser -- nothing is sent to any server.
- Results are computed using standard formulas and should be verified for critical applications.
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Area Calculator FAQ
What is area?
Area is the measure of a two-dimensional surface expressed in square units (like square meters, square feet, or square inches). It tells you how much space a flat shape covers.
How do I calculate the area of a rectangle?
Multiply the length by the width. Formula: Area = length × width. For example, a rectangle 5 meters long and 3 meters wide has an area of 15 square meters.
How do I calculate the area of a triangle?
Multiply the base by the height, then divide by 2. Formula: Area = (base × height) ÷ 2. For a triangle with base 8 cm and height 6 cm, the area is 24 square centimeters.
How do I calculate the area of a circle?
Multiply pi (π ≈ 3.14159) by the radius squared. Formula: Area = π × r². For a circle with radius 5 meters, the area is approximately 78.54 square meters.
What is the difference between area and perimeter?
Area measures the space inside a shape (in square units), while perimeter measures the distance around the outside (in linear units). For example, a room has area in square feet and perimeter in feet.
How do I convert between square feet and square meters?
1 square meter = 10.764 square feet. To convert square meters to square feet, multiply by 10.764. To convert square feet to square meters, divide by 10.764.
How do I calculate the area of an irregular shape?
Break the irregular shape into regular shapes (rectangles, triangles, etc.), calculate each area separately, then add them together. This method works for rooms, gardens, and complex floor plans.
What is the area of a square?
A square is a rectangle where all sides are equal. The area is side × side, or side². A square with 4-meter sides has an area of 16 square meters.
How do I find the area of a trapezoid?
Add the two parallel sides, multiply by the height, then divide by 2. Formula: Area = ((base₁ + base₂) × height) ÷ 2.
Why is π (pi) used in circle area calculations?
Pi (approximately 3.14159) is the ratio of a circle's circumference to its diameter. It appears in all circle calculations because it defines the fundamental relationship between a circle's dimensions.