Room & Measurement

Room Size Calculator

Calculate multi-section room area, perimeter, and cubic volume in square feet, square meters, square yards, and cubic units.

Room Sections

Measure rectangles, alcoves, or closets

Length (ft)

Width (ft)

Ceiling Height (ft) (optional for volume)

Total Room Measurements

Area, perimeter, and cubic volume

Total Floor Area

180 sq ft

16.72 m² (20 sq yards)

Perimeter

54 ft

Cubic Volume

1620 cu ft

Section Details:

Main Area (15×12 ft):180 sq ft

Total space covers 180 sq ft (16.7 m²) across 1 section.

How It Works & Calculation Formula

Formula Summary: Area = Σ(Length × Width). Perimeter = Σ 2(Length + Width). Volume = Area × Ceiling Height.

Step-by-Step Calculation:

Enter room length and width (or multiple sections for alcoves, closets, L-shapes).
Calculate area for each section: Section Length × Section Width.
Sum all sections for combined total floor area.
Calculate perimeter: 2 × (Length + Width).
Calculate cubic volume if ceiling height is entered: Floor Area × Ceiling Height.
Provide instant conversions between Imperial and Metric units.

Worked Example Calculation

Sample Inputs:

Section 1:15 ft × 12 ft
Section 2 (Alcove):6 ft × 4 ft
Ceiling Height:9 ft

Expected Output:

Total Area: 204.0 sq ft (19.0 m² / 22.7 sq yd). Perimeter: 74 ft. Volume: 1,836 cu ft (52.0 m³).

Practical Tips & Trade Guidelines

Measure rooms from baseboard to baseboard at floor level for maximum accuracy.
For rooms with closets or nooks, calculate each rectangular section individually and sum them up.
Knowing cubic volume is essential for sizing HVAC units, dehumidifiers, and air purifiers.
Always round up by 5–10% when estimating materials based on room area.

Frequently Asked Questions

Multiply square feet by 0.092903, or divide square feet by 10.7639. Our calculator converts both systems instantly.

Important Renovation Notice

Calculations are mathematical estimates based on standard trade conventions. Always field-verify room measurements, examine packaging labels, and check with a licensed contractor before purchasing materials or starting installation.