Square Footage Calculator
Calculate the area of any room or space in square feet and square meters at once. Add multiple rooms, handle rectangle, circle, and triangle shapes, allow for waste, and estimate flooring, paint, or tile cost. Works in feet/inches or metric — worldwide.
Pick your units and shape, enter the dimensions, and add as many rooms or areas as you need — the calculator totals them. Optionally add a waste allowance and a price per unit to estimate material cost.
Add each room or area; the calculator sums them. For an L-shaped room, split it into two rectangles.
| # | Shape | Dimensions | Square Feet | Square Meters |
|---|
* Area results are geometric estimates based on the dimensions you enter. For real projects, always add a waste allowance (commonly 5–10% for flooring, more for diagonal or patterned layouts), account for obstacles and offcuts, and confirm quantities with your supplier or contractor before purchasing. Cost figures are estimates only.
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What Is a Square Footage Calculator?
A square footage calculator works out the area of a room or space — how many square feet (or square meters) it covers. It's the essential first step for any flooring, carpet, tile, paint, landscaping, or real estate project, because almost everything you buy is priced by the square foot or square meter. Get the area right and you order the right amount of material; get it wrong and you either run short or waste money.
Our square footage calculator does more than a single box. It lets you add multiple rooms and totals them, handles rectangle, circle, and triangle shapes, shows the result in both square feet and square meters at once, adds a waste allowance, and can estimate your material cost from a price per unit.
How to Use This Square Footage Calculator
- Choose your units — feet (with inches), meters (with cm), or yards.
- Pick a shape — rectangle/square, circle, or triangle.
- Enter the dimensions for each room or area.
- Add more areas with "+ Add Room / Area" — the tool sums them all.
- Optional: add a waste % and a price per sq ft / sq m for a cost estimate.
How to Calculate Square Footage
For a rectangular room, square footage is simply length times width:
Circle: Area = π × radius² (radius = diameter ÷ 2)
Triangle: Area = ½ × base × height
Example: a room 12 feet by 10 feet is 12 × 10 = 120 square feet (about 11.15 square meters). If flooring costs $3.50 per square foot and you add 10% for waste, you'd need about 132 sq ft, costing roughly $462.
Measuring in Feet and Inches
Most rooms aren't whole feet. To convert inches to a decimal foot, divide by 12 — so 6 inches is 0.5 ft, and 3 inches is 0.25 ft. A wall that's 12 ft 6 in is 12.5 ft. Our calculator has separate feet and inches fields so you don't have to do this by hand. (In metric, centimetres convert the same way: divide by 100, so 50 cm = 0.5 m.)
Square Feet to Square Meters (and Back)
Working internationally? The conversions are fixed:
| From | To | Multiply By |
|---|---|---|
| Square feet | Square meters | 0.092903 |
| Square meters | Square feet | 10.7639 |
| Square feet | Square yards | 0.11111 |
| Square feet | Acres | 0.000022957 |
| Square meters | Hectares | 0.0001 |
Our calculator shows square feet and square meters together, plus square yards and acres, so you never have to convert manually.
How Much Waste Should I Add?
Always order more than the bare area to cover offcuts, mistakes, and future repairs. Common allowances:
- Standard flooring / carpet: add 5–10%.
- Diagonal or herringbone layouts: add 15–20% (more cutting).
- Tile with a pattern: add 10–15%.
- Wallpaper: add 10–15% to allow for pattern matching.
Enter your percentage in the waste field and the calculator shows the adjusted quantity to order.
Common Uses
- Flooring & carpet: how much to buy, and the cost.
- Paint: estimate wall or ceiling area (one gallon covers roughly 350–400 sq ft).
- Tile: floor and wall coverage with waste.
- Landscaping: turf, mulch, paving, or gravel areas.
- Real estate: total floor area of a home or unit.