Quickly compute area in square feet and square meters with our free Square Footage Calculator. Enter length and width, choose your units, and optionally add quantity and waste to get accurate totals for flooring, paint, turf, tile, mulch, and more.
How to use the Square Footage Calculator
Area for rectangles and most simple spaces is calculated using a straightforward formula: length multiplied by width. This calculator streamlines that process and adds practical features that contractors, DIYers, and planners use every day.
- Select the input unit (Feet, Inches, or Meters).
- Enter the length and width of the space in the same unit you selected.
- Set Quantity if you have multiple identical areas (for example, four rooms with the same dimensions).
- Add a Waste/Overage percentage if your project requires extra material for cuts, patterns, or future repairs.
- Choose your Output unit (square feet, square meters, or both) and pick the desired decimal precision.
- Click Calculate to get your result instantly.
Understanding square footage
Square footage is a measure of area commonly used in real estate, construction, landscaping, and interior projects. Knowing the exact square footage helps you estimate material quantities, budget costs, and plan labor. While many spaces are perfect rectangles, irregular rooms can be split into multiple rectangles and calculated separately, then summed for a total.
Common use cases
- Flooring and carpets: determine how many boxes or rolls to order.
- Paint coverage: estimate wall or ceiling coverage when paired with wall height.
- Tile and decking: plan material with the right overage.
- Landscaping: calculate sod, mulch, rock, or turf coverage.
- Real estate: compare home sizes or rooms accurately.
Formulas and unit conversions
For a rectangular area, the base formula is: Area = Length × Width. This calculator lets you work in feet, inches, or meters and can display results in square feet or square meters.
- 1 foot = 12 inches
- 1 meter ? 3.2808399 feet
- 1 square foot ? 0.09290304 square meters
If you measure in inches, the calculator converts to feet under the hood to keep results consistent. Measuring in meters? It converts to feet for the intermediate calculation and back to square meters if requested.
Why add waste/overage?
Most projects require a buffer. Patterns, cuts, defects, and future repairs can all increase the material you need beyond the exact square footage. A typical overage is 5–15% depending on the material and layout complexity. Our Square Footage Calculator lets you add this percentage so you can order confidently and avoid delays.
Pro tips for accurate results
- Measure twice, enter once: confirm both length and width before calculating.
- Round up material orders to the nearest full package after adding waste.
- Break complex rooms into rectangles and sum the areas.
- Use a consistent unit for all measurements.
- Record your measurements and results for future reference.
Examples
Suppose your room is 12 ft by 10 ft. Base area is 120 sq ft. With 10% waste, you should plan for 132 sq ft. If you have three identical rooms, total base area is 360 sq ft, and with 10% waste it becomes 396 sq ft.
When to choose square meters
Working with international suppliers or metric plans? Select meters as your input and show results in square meters to match spec sheets, while still seeing square feet if you choose the Both option.
With clear inputs and instant results, this Square Footage Calculator helps you plan projects, control costs, and minimize surprises.