Room Square Foot Calculator
Find out exactly how many square feet your room is. Select a room preset or enter custom dimensions.
How to Measure Your Room
Measuring a room's square footage is straightforward. All you need is a tape measure and these simple steps:
- Clear the edges: Move furniture away from the walls so you can measure along the full length.
- Measure the length: Run your tape measure along the longest wall from one corner to the opposite corner.
- Measure the width: Measure the shorter wall perpendicular to the length.
- Multiply: Length × Width = Square Footage.
For example, a bedroom that is 12 feet long and 10 feet wide has an area of 120 square feet.
Odd-Shaped Rooms
If your room is L-shaped or has alcoves, divide it into rectangles, calculate each separately, and add them together. Or use our odd shapes calculator.
Room Square Footage for Flooring and Renovation
Knowing your room's exact square footage is the first step in any renovation project. Whether you're buying hardwood, laying tile, ordering carpet, or painting walls, every material estimate starts with the floor area.
How to Add 10–15 % Waste for Flooring
Never order only the exact square footage. Cutting planks or tiles to fit around edges, doorways, and corners wastes material. Add the following percentages on top of your measured area:
| Flooring Type | Recommended Waste Factor |
|---|---|
| Hardwood / Laminate (straight lay) | 10 % |
| Vinyl / LVP | 10 % |
| Tile (straight lay) | 10 % |
| Tile (diagonal / herringbone) | 15–20 % |
| Carpet | 10 % + round up to nearest yard |
Standard Room Sizes Reference Guide
Not sure if your measurements are typical? Compare against these standard room dimensions used in US residential construction. If your result falls within the range, you're on the right track.
| Room Type | Typical Dimensions | Square Feet |
|---|---|---|
| Small Bedroom | 10 × 10 ft | 100 sq ft |
| Standard Bedroom | 12 × 12 ft | 144 sq ft |
| Master Bedroom | 14 × 16 ft | 224 sq ft |
| Full Bathroom | 8 × 10 ft | 80 sq ft |
| Half Bath / Powder Room | 5 × 8 ft | 40 sq ft |
| Kitchen (small) | 10 × 12 ft | 120 sq ft |
| Kitchen (average) | 12 × 14 ft | 168 sq ft |
| Living Room (average) | 16 × 20 ft | 320 sq ft |
| Dining Room | 12 × 14 ft | 168 sq ft |
| Home Office | 10 × 12 ft | 120 sq ft |
Tips for Accurate Room Measurements
A small measuring error compounds quickly when ordering materials. Follow these best practices to ensure your room square footage is spot-on:
- Use a laser measure: Laser distance meters (available for under $30) are faster and more accurate than tape measures for large rooms.
- Measure at floor level: Baseboards, door frames, and cabinets can throw off measurements taken at height. Always measure along the floor plane.
- Double-check by measuring twice: Measure each wall twice in opposite directions and use the average if they differ.
- Account for alcoves and bay windows: Include these in your total if you'll be laying flooring there. Calculate them as separate rectangles and add to the main room area.
- Record in decimal feet: Convert inches to decimal feet before multiplying. 6 inches = 0.5 ft, so a 12 ft 6 in room = 12.5 ft.
Useful Formula: Feet and Inches to Decimal Feet
Example: 11 ft 9 in = 11 + (9 ÷ 12) = 11 + 0.75 = 11.75 ft. Or use our Feet & Inches Calculator to skip this step entirely.
All Square Foot Calculators
Choose a specialized calculator for your specific project type.
Frequently Asked Questions
Measure the length and width of the room in feet and multiply them together. For example, a 10×12 room is 120 sq ft.
Break the room into smaller rectangles or triangles, calculate each area separately, and add them up. Our odd shapes calculator can help.
A 10×10 room is exactly 100 square feet (10 × 10 = 100).
It depends on your purpose. For flooring, include any area you'll be covering. For real estate listings, closets are typically included in the room's square footage.