Calculate wall or surface area, including a single opening where appropriate. Use your paint manufacturer’s coverage guidance to estimate paint quantity.
仕組み
1
形状の選択
Choose the shape that matches your space.
2
寸法を入力してください
測定値を任意の単位で入力します。数量、廃棄係数、材料価格を追加します。
3
結果を取得する
面積 (ft²、in²、yd²、m²、エーカー) とコスト見積もりをすべて一度に表示します。
よくある質問
How do I calculate square footage for painting?
Measure height and width of each wall. Multiply for each wall and add. Subtract windows and doors. Wall with Window subtracts openings for you.
How much paint do I need per square foot?
One gallon covers about 350 to 400 sq ft per coat. For two coats, divide total wall area by 175 to 200. Example: 800 sq ft ÷ 175 ≈ 4.5 gallons for two coats.
Should I subtract windows and doors from wall area?
Yes. A standard door is about 21 sq ft (3 × 7 ft). A standard window is about 12 sq ft (3 × 4 ft). Subtract those from total wall area, or use Wall with Window to do it automatically.
How do I calculate paint for exterior walls?
Measure length and height of each exterior wall and multiply. Subtract windows and doors. Add all walls. Exterior coverage is similar to interior (350 to 400 sq ft per gallon), but texture can need up to 50% more paint.
How do I calculate paint for a room with vaulted ceilings?
For the sloped wall, use Cathedral Wall. Enter base width, left wall height, and right wall height. The calculator applies the trapezoid formula for that surface.