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Room Size Calculator

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Room Size Calculator

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Need to measure a room for flooring, paint, furniture, or renovation? Our Room Size Calculator helps you quickly calculate the square footage or square meters of any room. Just enter your room’s dimensions, and the calculator does the rest.

Whether you're preparing for a home project, estimating materials, or checking if your furniture will fit, this tool saves time and avoids guesswork.

How to Calculate Room Size

The basic formula to calculate a room’s area is:

Area = Length × Width

If you want to calculate volume, use:

Volume = Length × Width × Height

Example (Rectangular Room):

  • Length: 12 ft
  • Width: 10 ft
  • Area: 120 sq ft

Measuring Tips

  • Use a measuring tape or laser tool for accuracy
  • Measure from wall to wall, not floor to ceiling
  • If the room has irregular shapes, divide it into rectangles and calculate each separately
  • Convert feet to inches or meters as needed

Room Size by Purpose (Average Dimensions)

Room Type Average Size (ft) Area (sq ft)
Bedroom10 × 12120
Living Room15 × 20300
Kitchen12 × 15180
Bathroom6 × 848
Dining Room12 × 14168

Room Volume Calculator

If you're measuring for heating, cooling (BTU), or acoustic treatments, calculate the room volume:

Volume = Length × Width × Height

Example: A 10 × 12 room with 8 ft ceiling = 960 cubic feet

Metric Conversion

If you're working in meters:

  • 1 ft = 0.3048 m
  • 1 sq ft = 0.0929 m²
  • 1 cubic foot = 0.0283 m³

Common Use Cases for a Room Size Calculator

  • Buying the right amount of flooring (tile, carpet, laminate)
  • Estimating paint coverage
  • Ensuring furniture fits your space
  • Determining heating or cooling needs
  • Interior design layout planning

FAQs About Measuring Room Size

How do I measure a room in square feet?

Measure the length and width in feet, then multiply them together. For example, 12 ft × 10 ft = 120 sq ft.

How do I measure a room with odd shapes?

Break the space into rectangles or triangles, calculate each area separately, then add them together for total square footage.

What is the standard room size?

It varies by purpose. Bedrooms are typically 10×12 ft, while living rooms can be 15×20 ft or more.

What is room volume and why does it matter?

Room volume is the three-dimensional space (cubic ft or m³). It matters for HVAC sizing, acoustics, and storage planning.

Should I include closets in room measurements?

Only if you’re calculating total usable floor space or material coverage (like flooring).

Final Thoughts

Our Room Size Calculator makes it easy to plan your next project, from painting and decorating to installing new flooring or setting up a home theater. Accurately measuring your room saves money, avoids waste, and helps you make smart decisions before buying materials or furniture.