Paint Calculator – Estimate the Right Amount of Paint for Your Walls
One of the most common challenges while starting a painting project is figuring out how much paint you really need. Buying less paint can interrupt your project midway, while buying too much leaves you with unused cans and wasted money. That’s where our paint calculator comes in handy. It helps you estimate the right amount of paint based on your wall dimensions, number of coats, and surface exclusions like doors and windows. With this tool, you can plan better, save costs, and achieve a flawless finish.
How to Use Our Paint Calculator
Our wall paint calculator is simple yet highly effective. Here’s how you can use it step by step:
- Choose your unit of measurement: Select either meters (m) or feet (ft) depending on your preference.
- Enter wall dimensions: Input the length and height of each wall. If you have multiple walls, you can add them separately.
- Account for doors and windows: Add the number of doors and windows so their areas are automatically subtracted from the total paintable surface.
- Specify the number of coats: Usually, two coats are recommended for even coverage and long-lasting results.
- Get instant results: The calculator will display the total paint required in liters and gallons along with a detailed breakdown of wall area, excluded area, and final paintable area.
Key Factors That Affect Paint Quantity
A reliable paint coverage calculator considers several factors before giving you the final estimate:
1. Wall Surface Area
The basic formula is straightforward: Wall Area = Length × Height. Our tool calculates this for each wall and adds them up to get the total surface area.
2. Non-Paintable Areas (Doors and Windows)
You don’t paint over openings, so these areas must be excluded. For ease, our tool uses average sizes:
- Door area: ~1.95 sq. meters (21 sq. feet).
- Window area: ~1.4 sq. meters (15 sq. feet).
This ensures your room paint calculator only estimates for surfaces that actually need painting.
3. Paint Coverage Capacity
Coverage refers to how much area a specific amount of paint can cover. On average:
- 1 liter of paint covers around 10 sq. meters (107 sq. feet).
- 1 gallon of paint covers around 37 sq. meters (400 sq. feet).
Keep in mind: rough walls or dark-to-light color changes might require extra paint.
4. Number of Coats
One coat is rarely enough. For best results, two coats are standard. In some cases, a primer coat may also be necessary. Our calculator multiplies the paintable area by the number of coats for accuracy.
Paint Calculation Formula
Our paint estimator follows this logical flow:
- Find the total wall area.
- Subtract the area of doors and windows.
- Multiply the paintable area by the number of coats.
- Divide the result by the coverage rate of your paint (liters or gallons).
Frequently Asked Questions (FAQ)
Should I buy exactly the amount shown in the results?
It’s best to buy a little extra (around 10%) to cover for touch-ups, wall texture differences, or minor errors.
Can this calculator be used for ceilings?
Yes. Just treat the ceiling as another wall—enter its length and width as dimensions and the calculator will do the rest.
What if my windows or doors are not standard size?
If your openings are larger or smaller, measure their area manually (Length × Height) and adjust the wall area accordingly for best results.
How much area does 1 liter of paint cover?
On average, 1 liter of interior paint covers about 10 square meters with a single coat.
Conclusion
Painting projects don’t need to be stressful. With our paint calculator, you can easily figure out the exact amount of paint you’ll need, avoid overspending, and achieve professional-quality results. Use this tool before your next project and paint with confidence!