Rectangle Perimeter Calculator
Calculate the perimeter of a rectangle by adding up all four sides. Perfect for construction, framing, fencing, and fabric planning where you need to know the total boundary length.
Calculate Rectangle Perimeter
Enter the length and width of your rectangle:
P = 2 Γ (length + width)
This adds up all four sides: length + width + length + width
Understanding Rectangle Perimeter
The perimeter of a rectangle is the total distance around its boundary. Since a rectangle has four sides with opposite sides being equal, the perimeter is calculated by adding all four sides together or using the formula P = 2 Γ (length + width).
Rectangle Properties
π² Rectangle Definition
A rectangle is a four-sided polygon with opposite sides equal and all interior angles measuring 90 degrees. The perimeter represents the total length of all four sides combined.
π Perimeter Formula
P = 2 Γ (length + width)
This formula works because a rectangle has two pairs of equal sides: two lengths and two widths.
π Related Properties
Area = length Γ width
Diagonal = β(lengthΒ² + widthΒ²)
Aspect ratio = longer side Γ· shorter side
π‘ Pro Tip: When length equals width, you have a square! The perimeter formula still works: P = 4 Γ side length, since all four sides are equal.
Common Rectangle Examples
| Length | Width | Perimeter | Use Case |
|---|---|---|---|
| 5 m | 3 m | 16 m | Standard room |
| 10 ft | 8 ft | 36 ft | Large bedroom |
| 20 m | 15 m | 70 m | Living room |
| 8.5 in | 11 in | 39 in | Letter paper |
| 297 mm | 210 mm | 1,014 mm | A4 paper |
| 12 ft | 12 ft | 48 ft | Square room |
Perimeter vs Area
π Perimeter
Measures the total length around the outside of the rectangle
Units: linear units (meters, feet, inches)
Used for: fencing, framing, trim, border materials
π Area
Measures the space inside the rectangle
Units: square units (mΒ², ftΒ², inΒ²)
Used for: flooring, paint, carpet, wall covering
π Relationship
Two rectangles can have the same perimeter but different areas
Example: 5Γ3 and 4Γ4 rectangles both have perimeter 16, but areas 15 and 16
Real-World Applications
ποΈ Construction & Carpentry
Fence installation around property
Baseboard and crown molding
Picture frame construction
Door and window trim
Deck railing calculations
π Home Improvement
Garden bed construction
Tile border installation
Wallpaper planning
Flooring trim calculations
Room painting (paint quantity)
π Manufacturing
Sheet metal cutting and bending
Packaging material requirements
Frame and chassis construction
Material waste minimization
Product design planning
π Design & Planning
Blueprint and architectural drawings
Garden and landscape planning
Art and graphic design projects
Model building and prototyping
Real estate property measurements
Construction Examples
| Project | Dimensions | Perimeter Needed | Materials |
|---|---|---|---|
| Backyard fence | 20m Γ 15m | 70m of fencing | Wood posts, wire mesh |
| Picture frame | 30cm Γ 40cm | 140cm of molding | Wood or plastic molding |
| Tile border | 3m Γ 2m | 10m of border tiles | Decorative tile strips |
| Room baseboard | 4m Γ 3m | 14m of baseboard | Wood or composite trim |
| Garden bed | 2m Γ 1.5m | 7m of edging | Plastic or stone edging |
Special Rectangle Cases
β¬ Square
When length = width
P = 4 Γ side length
All four sides equal
Diagonal = side Γ β2
π Long Rectangle
When length β« width
P β 2 Γ length
Width contribution minimal
Common in corridors, hallways
π Golden Rectangle
Aspect ratio β 1.618
Length/width = Ο (golden ratio)
Aesthetically pleasing proportions
Found in art and architecture
Unit Conversions
| From | To | Multiply by | Example |
|---|---|---|---|
| Meters | Feet | 3.28084 | 10m = 32.81ft |
| Feet | Meters | 0.3048 | 10ft = 3.05m |
| Inches | Centimeters | 2.54 | 12in = 30.48cm |
| Centimeters | Inches | 0.393701 | 30cm = 11.81in |