📐 Rectangle Area Calculator

Calculate area, perimeter, and diagonal

Unit of Measurement

Length (ft)

Width (ft)

Rectangle Formulas

Area

Area = Length × Width

Example: 10 ft × 6 ft = 60 sq ft

Perimeter

Perimeter = 2(Length + Width)

Example: 2(10 + 6) = 2(16) = 32 ft

Diagonal

Diagonal = √(Length² + Width²)

Example: √(10² + 6²) = √136 ≈ 11.66 ft

Common Rectangle Sizes

Standard Door

3' × 7'

21 sq ft

Twin Bed

39" × 75"

20.3 sq ft

Full Bed

54" × 75"

28.1 sq ft

Queen Bed

60" × 80"

33.3 sq ft

King Bed

76" × 80"

42.2 sq ft

Parking Space

9' × 18'

162 sq ft

Tennis Court

78' × 36'

2,808 sq ft

Soccer Field

100m × 64m

6,400 m²

Real-World Applications

🏗️ Construction

• Room size calculations
• Flooring material needed
• Paint coverage estimates
• Carpet/tile requirements

🌳 Landscaping

• Lawn/turf area
• Mulch or gravel needed
• Garden bed sizing
• Patio/deck dimensions

🏠 Real Estate

• Property square footage
• Room measurements
• Lot size calculations
• Living space area

🎨 Design

• Canvas sizing
• Poster dimensions
• Banner/sign area
• Fabric requirements

Square vs Rectangle

Rectangle

• Four sides, four right angles
• Opposite sides equal
• Length ≠ Width
• Area = L × W

Square (Special Rectangle)

• Four sides, four right angles
• All sides equal
• Length = Width
• Area = Side²

Quick Examples

10 × 5

Area: 50 sq units • Perimeter: 30 units

12 × 8

Area: 96 sq units • Perimeter: 40 units

15 × 10

Area: 150 sq units • Perimeter: 50 units

20 × 15

Area: 300 sq units • Perimeter: 70 units

25 × 12

Area: 300 sq units • Perimeter: 74 units

30 × 20

Area: 600 sq units • Perimeter: 100 units

How to Use This Calculator
1
Enter Your Values
Input the required values in the calculator fields above. Make sure all inputs are valid numbers.
2
Click Calculate
Press the "Calculate" button to perform the calculation and see your results.
3
Review Results
Review the calculated results displayed below. Use these values for your needs.
About Rectangle Area Calculator
The Rectangle Area Calculator is a useful tool for calculating rectangle area values. This calculator helps you quickly and accurately determine the results you need for your calculations.
When to Use This Calculator
Quick Calculations: Get instant results without manual computation
Accuracy: Ensure precise calculations every time
Planning: Use for project planning and estimation
Verification: Double-check your manual calculations
Why Use Our Calculator?
✅ Instant Results: Get accurate calculations immediately
✅ Easy to Use: Simple interface for all skill levels
✅ 100% Free: No registration or payment required
✅ Mobile Friendly: Works on all devices
✅ Accurate: Precise mathematical calculations
Tips for Best Results
Double-Check Inputs: Verify all values before calculating
Use Valid Numbers: Ensure inputs are valid numbers
Review Results: Check results for reasonableness
Clear and Retry: Clear inputs if you need to recalculate
Frequently Asked Questions

What's the difference between area and perimeter?

Area is the space inside (measured in square units). Perimeter is the distance around the outside (measured in linear units). Area = L×W, Perimeter = 2(L+W).

How do I convert square feet to square meters?

Divide by 10.764. Example: 100 sq ft ÷ 10.764 = 9.29 m². To go the other way, multiply by 10.764.

Can a rectangle have equal length and width?

Yes! When length equals width, the rectangle is a square. A square is a special type of rectangle where all four sides are equal.

How do I find the diagonal of a rectangle?

Use the Pythagorean theorem: diagonal = √(length² + width²). The diagonal creates two right triangles within the rectangle.

How much flooring do I need for a room?

Calculate the area (length × width), then add 10% for waste and cuts. Example: 12' × 15' = 180 sq ft + 18 sq ft (10%) = 198 sq ft total.