Calculate area for flooring, painting, and landscaping
About Square Footage Calculator
A square footage calculator finds the area of a room or space for flooring, painting, tiling, or landscaping projects, and can account for multiple rooms or irregular layouts by adding sections together. Getting square footage right avoids under-ordering materials mid-project.
Formula
Square Footage = Length (ft) × Width (ft)
How It Works
Measure the length and width of each room or section in feet
Multiply length by width to get that section's square footage
For irregular rooms, split the space into rectangles, calculate each separately, and add them together
For multiple rooms, add each room's square footage for a project total
Tips
Always round up your material order slightly (5-10%) to account for cuts, waste, and pattern matching, especially for tile and flooring
Measure at the widest points of a room, including alcoves and closets if they'll be covered by the same material
For flooring sold by the box (covering a fixed square footage per box), divide total square footage by coverage per box and round up to a whole box
Frequently Asked Questions
How do I calculate square footage for an L-shaped room?
Divide the room into two or more rectangles, calculate the square footage of each rectangle separately (length × width), then add the results together for the total.
How much extra material should I order beyond calculated square footage?
A common rule is 10% extra for standard installations, and up to 15-20% for diagonal patterns, herringbone layouts, or rooms with many cuts and angles.
How do I convert square feet to square yards for carpet?
Divide square feet by 9 (since 1 square yard = 9 square feet). For example, 450 square feet ÷ 9 = 50 square yards.
Does square footage include closets and alcoves?
Include them if they'll be covered by the same material — measure and add their square footage just like any other section of the room.
How many boxes of tile or flooring do I need?
Divide total square footage (plus your waste allowance) by the coverage per box listed on the product, then round up to the next whole box, since partial boxes generally aren't available.