Area Calculator

Multiply length by width, both in the same unit. If your length and width are in feet, the result is square feet. If they're in inches, the result is square inches. To convert square inches to square feet, divide by 144.

This calculator handles the conversion automatically. Enter dimensions in feet and inches the way you measured them, and you get a result in square feet.

For most jobs, you're not buying material or doing work over a door or window opening. If you're painting a wall with a window in it, you need paint for the wall minus the window. If you're drywalling a ceiling with a recessed light cutout, you don't need drywall over the cutout.

Subtracting openings up front gives you an accurate material list and a cleaner labor estimate. Especially helpful when you're bidding work.

As many as you need. There's no fixed limit. Add a surface for every wall, ceiling, floor, soffit, or section you're working on. Each surface can have as many openings as it actually has.

For a typical room, you might end up with four walls and a ceiling, each with one or two openings. For a whole-house repaint, you might have thirty or forty surfaces. The calculator handles both.

Each surface card shows its own net area as soon as you've filled in length and width. That's the area of that one surface minus its openings.

The grand total only appears when you press Calculate. It's the sum of all your surfaces. Splitting it this way lets you sanity-check individual rooms or walls while you work, and get the rolled-up total when you're ready.

Yes. A floor is just a surface with length and width like any other. If your floor has obstructions you don't want to count, like a built-in island or a stair opening, add them as openings on the floor surface.

The math doesn't care whether it's a wall, floor, or ceiling. It's all area.