Square Footage Calculator: Area in Square Feet

Worked examples

12 ft by 10 ft room

12 × 10 = 120 sq ft, which is about 11.15 sq m. At $4.50 per sq ft, flooring runs about $540.00.

Two rooms combined

A 15 × 12 ft living room (180 sq ft) plus a 10 × 10 ft bedroom (100 sq ft) totals 280 sq ft.

Dimensions in inches

A 96 in by 48 in countertop is 8 ft by 4 ft, so 32 sq ft.

A patio measured in meters

A 4 m by 3 m patio is about 13.12 ft by 9.84 ft, giving roughly 129.2 sq ft (12 sq m).

How the square footage calculator works

Square footage is just area measured in square feet. For any rectangle, the formula is a single multiplication:

Square footage = length × width

Measure both sides in the same unit and multiply. A room that is 12 feet long and 10 feet wide is 12 × 10 = 120 square feet.

Working in other units

Tape measures and plans do not always come in feet. This tool converts each dimension to feet first, then multiplies:

1 inch = 1/12 foot (12 inches make a foot)
1 yard = 3 feet
1 meter ≈ 3.28084 feet

So a countertop measured as 96 inches by 48 inches becomes 8 ft by 4 ft, which is 8 × 4 = 32 sq ft. A patio that is 4 m by 3 m converts to roughly 13.12 ft by 9.84 ft, or about 129 sq ft.

To read the result the other way, square meters = square feet ÷ 10.7639. That is why 120 sq ft shows as about 11.15 sq m.

Adding multiple rooms

Homes are rarely one clean rectangle. Use the Add area button to include a row for each room or section, and the total updates as you type. An L-shaped room is two rectangles: measure each part, enter both, and the calculator sums them.

For example, a 15 × 12 ft living room is 180 sq ft and a 10 × 10 ft bedroom is 100 sq ft, for a combined 280 sq ft. Any blank or non-positive dimension simply counts as zero for that row, so a half-finished entry never breaks the total.

Estimating flooring, paint, and turf cost

Once you have a total area, most material pricing is per square foot. Enter a price per sq ft and the calculator multiplies it by your total to estimate cost:

Estimated cost = total square feet × price per sq ft

At $4.50 per sq ft, 120 sq ft of flooring is 120 × 4.50 = $540.00. The same total works for laminate, tile, carpet, artificial turf, or a rough paint estimate once you know coverage.

A practical tip: order 5-10% more material than the raw square footage to cover offcuts, breakage, and mistakes, and more for diagonal or patterned layouts. Paint is sold by coverage per gallon rather than per square foot, so divide your wall area by the coverage on the can (often around 350-400 sq ft per gallon per coat) to get the number of gallons.

A note on accuracy

These figures are estimates for planning and budgeting. Measure carefully, round up when buying materials, and check a supplier’s own coverage and waste guidance before ordering.

Frequently asked questions

How do I calculate square footage?

Measure the length and width of the area in the same unit, then multiply them. For a rectangle, square footage = length × width. A room that is 12 feet long and 10 feet wide is 12 × 10 = 120 square feet.

How do I find the square footage of an irregular room?

Split the space into rectangles, calculate each one separately, then add them together. This calculator lets you add a row per rectangle and keeps a running total, so an L-shaped room becomes two rectangles you sum automatically.

How do I convert square feet to square meters?

Divide square feet by 10.7639. So 120 sq ft ÷ 10.7639 is about 11.15 sq m. The calculator shows both figures at once.

How much extra material should I buy for flooring?

Add 5-10% to your total square footage for cuts, waste, and mistakes, and a bit more for patterned or diagonal layouts. If your rooms total 280 sq ft, ordering around 300 sq ft is a safe buffer.

Can I measure dimensions in different units?

Yes. Pick the unit per area (feet, inches, yards, or meters) and the calculator converts everything to square feet and square meters before adding it up, so you can mix a room measured in feet with a slab measured in meters.