Square Footage Calculator

Square footage is floor area — the number of one-foot squares that tile a flat surface. It is the price unit of real estate, the ordering unit for flooring and paint, and the dimension that decides whether a couch fits. Despite its ubiquity it is routinely mismeasured, so this calculator removes the multiplication from the equation — enter length and width in feet or metres, and read the area in square feet and square meters.

The formula

Square footage = length × width

Both sides must be in the same unit. If you measured in metres, multiply every dimension by 3.28084 first (1 m = 3.28084 ft); the calculator does this conversion automatically and reports both unit pairings.

Worked example

A room 10 ft × 12 ft:

Area = 10 × 12 = 120 square feet
120 ÷ 10.7639 ≈ 11.15 square meters

Quick conversions

• 1 ft² = 144 in²
• 1 m² = 10.7639 ft²
• 1 sq yard = 9 ft²
• 1 acre = 43,560 ft²
• Regional units: 1 marla ≈ 272.25 ft² (north India/Pakistan), 1 cent = 435.6 ft² (south India), 1 gaj ≈ 9 ft²

Buying materials: don't stop at the area

The pure geometry is only the start — purchases add a waste margin:

• Flooring — order about 10% extra for cutting and mistakes: a 120 sq ft room needs roughly 132 sq ft of tiles or planks.
• Paint — a gallon covers roughly 350 sq ft per coat; two coats double the order.
• Carpet and underlay — rooms rarely arrive in clean rectangles, and roll widths force joins that the extra 10% absorbs.

Measuring irregular and L-shaped rooms

Split an odd room into rectangles, size each, then add the results. The calculator handles one rectangle at a time — for an L-shape, compute both rectangles and sum. For a round dining area, approximate with radius × radius × π. Handle alcoves, closets and built-ins separately, and decide up front whether doorways count.

Measuring without a tape

No measuring tape handy? Use the room itself as the ruler: standard residential doors are about 3 ft wide, floor tiles are often 1 or 2 ft, and a typical adult stride is close to 2.5 ft. Counting tiles or steps across a room lands within a few percent of a taped measurement — good enough to sanity-check a broker's quote before you commit to buying material.

The real-estate vocabulary trap

Realtors quote three different square footages for the same flat:

• Carpet area — inside the walls, what you can actually use.
• Built-up area — carpet area plus the wall thickness.
• Super built-up area — adds marketing-allowed common spaces (lobbies, stairs).

Two brokers can quote the same apartment differently and both be technically honest about their terms. Always ask which definition is being priced — comparing "sq ft rates" from different definitions invalidates the comparison.

Common mistakes

• Measuring in two units — a 10-foot wall against a 2.5-metre wall — and multiplying the raw numbers.
• Including full wall thickness when the requirement is carpet area.
• Forgetting alcoves and closets from the total.
• Confusing area with volume — for a box's volume, use the cubic feet calculator.

Practical use cases

• Property comparisons and rent benchmarking ("₹ per sq ft" is the standard metric).
• Flooring, tiling, carpet and paint purchase orders.
• Furniture and appliance fit checks — will the sofa clear the doorway and the wall?
• Office and warehouse planning — how much room does this activity actually need?

Enter the two dimensions in feet or metres and let the calculator convert and multiply.