About Paint Calculator
This calculator estimates the amount of paint required for walls and ceiling. Each standard door (~21 sq ft) and window (~15 sq ft) is subtracted from the wall area. Paint coverage is estimated at 11 sq metres per litre per coat.
For best results, always buy slightly more paint than calculated — touch-ups and uneven surfaces can increase consumption. One gallon = 3.785 litres.
When to Use This Calculator
Painting a new home: Moving into a 3-bedroom house? Calculate each room individually to total up your paint order. A typical living room (15x12 ft) needs about 6-7 litres for two coats, while a small bathroom (7x5 ft) might need just 2-3 litres.
Refreshing a rental property: Landlords repainting between tenants need accurate estimates to control costs. A 2-bedroom apartment (around 700 sq ft of wall area) typically requires 10-12 litres of paint for two coats.
Planning an accent wall: Not painting the whole room? Just measure that single wall's width and height, set doors and windows to zero, and you'll know exactly how much paint to buy for your feature wall project.
How to Use the Paint Calculator
Imagine you're painting a 12x10 ft bedroom with 8 ft ceilings, one door, and two windows. Enter the room length (12), width (10), and height (8). Input 1 door and 2 windows — each door saves you about 21 sq ft of painting, each window about 15 sq ft. For most rooms, 2 coats of paint gives a professional finish, especially if you're switching from a dark to a light color. Hit calculate, and you'll see you need about 5.4 litres of paint. That means two 2.5-litre tins plus a small 1-litre tin should cover it. If your room has a vaulted ceiling or unusual features, measure the actual wall height at the tallest point.
Tips for Buying Paint
Always buy slightly more paint than the calculator says — touching up missed spots or fixing roller splatter uses more than you think. High-traffic areas like hallways and kitchens benefit from washable finishes (eggshell or satin). Keep a record of the exact color code and brand you used; trust me, matching paint a year later is nearly impossible without it. For textured walls, add about 10% to your total because the surface absorbs more paint. And never store paint in extreme temperatures — a cool, dark cupboard keeps leftovers usable for touch-ups.