Room Project Calculator
Enter a room's dimensions once — get floor area, wall area, perimeter, and volume, then continue straight into Paint, Flooring, Drywall, or Insulation with those dimensions already filled in.
Continue your project
These dimensions carry over automatically.
How this is calculated
Perimeter = 2 × (length + width). Wall area = perimeter × height. Volume = floor area × height. Floor and ceiling area both equal length × width.
Wall area here is the gross area, before subtracting doors and windows — the calculators you continue into do that for you.
One room, every calculation
Planning a renovation usually means re-measuring the same room for every material — paint, flooring, drywall, insulation. Enter it once here, and each linked calculator starts with your room's length, width, and height already filled in.
Frequently asked questions
What can I do with these numbers?
Use the "continue to..." links below to jump into Paint, Flooring, Drywall, or Insulation with this room's dimensions already filled in — no need to measure or type them again.
Why is wall area a flat perimeter x height, with no doors or windows?
This page gives you the room's raw geometry. Once you continue into Paint or Drywall, those calculators subtract standard door and window allowances for you.
What is room volume useful for?
Volume (floor area × height) is useful for sizing heating/cooling loads, air changes, or bulk materials like loose-fill insulation — most day-to-day material calculations use area instead.
Related calculators
Paint Calculator
Calculate how much paint you need for a room, including doors, windows, coats, and cans.
Flooring Calculator
Calculate how many planks, tiles, and boxes of flooring you need for a room.
Drywall Calculator
Calculate how many drywall sheets, screws, and joint compound buckets you need for a room.
Insulation Calculator
Calculate how many rolls, batts, or bags of insulation you need for an area.