How Much Paint Do I Need Calculator

How Much Paint Do I Need Calculator

Height of Walls (ft):
Sum Total Length of Walls (ft):
Number of Doors:
Number of Windows:
Number of coats of paint:
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How Much Paint Do I Need Formula:

Wall area - 20 square feet per door - 15 square feet per window. All of this multiplied by the number of coats and divided by 350 square feet per gallon.

How Much Paint Do I Need Definition

One of the least expensive ways to update your home is by painting. It is probably the most cost effective method as well, but you really need to know how much paint you actually need. If you buy too much paint, you will have wasted some money. If you do not buy enough paint, you will have to return to the store to get more. Take a quick moment to calculate your paint needs now!

The basic formula for deciding how much paint you need is simple for the wall area. You need to figure out the dimensions of your room. Multiply the length and the width of your room. Once you have that information, subtract 20 square feet for each door in the room and 15 square feet per window. A gallon of paint typically covers about 350 square feet. Take the wall area and divide it by 350 to find the amount of paint that you will need to paint one coat. No need to do these calculations on a piece of paper of a standard calculator. Simply enter the below inputs into the calculator for a quick easy calculation!

How to Use the Calculator

The first inputs of the above paint calculator, you will be asked for the height and length of your walls. You put in that information along with the number of doors and windows that are in the room. Remember that this calculator is based upon the standard measurements. Oddly shaped windows may skew the results, so take that into consideration. You will then have to put in the number of coats that you expect to paint. In most cases, two coats of paint are usually plenty.

1. Height of the Walls

The height of the walls is measured in feet. The calculator also assumes that you have perfectly rectangular or square rooms. If you have slanted ceilings, you may need less paint than the calculator figures. To get this measurement, use a tape measure to measure the distance from the ceiling to the floor. Most walls are 8 or 10 feet high.

2. Length of the Walls

The length of the walls will vary, and they are also measured in feet. If you have a rectangular room, you will only need to measure the one side and double it. A square room will only require you to measure one wall and multiply that number by four. The length of walls is not typically a standard measurement. You will likely get the best measurement if you have someone else help you to hold the measuring tape.

3. The Number of Doors

For this part of the calculation, you will need to simply type in the number of doors that you have. French doors will count as two doors. Be sure to include any closet doors in the calculation as well.

4. The Number of Windows

Simply count all of the windows in the room that you are going to paint. Remember that the calculator is based upon a standard fifteen square foot window. Add that number to the calculator.

5. Number of Coats of Paint

The typical number of coats is two. If you are going over a darker color with a lighter color, you may require some additional coats. Putting a darker color over a lighter color may only require one coat. It is best to plan on two coats, but add or subtract at least one coat if you are drastically changing the color scheme.


Once all of the information is in the online calculator, click on the calculate button. Your results will be given to you and you can head to the store to get your paint. Also, check out the Circular Room Paint Calculator!

How to Calculate How Much Paint Do I Need

Let's be honest - sometimes the best how much paint do i need calculator is the one that is easy to use and doesn't require us to even know what the how much paint do i need formula is in the first place! But if you want to know the exact formula for calculating how much paint do i need then please check out the "Formula" box above.

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You can get a free online how much paint do i need calculator for your website and you don't even have to download the how much paint do i need calculator - you can just copy and paste! The how much paint do i need calculator exactly as you see it above is 100% free for you to use. If you want to customize the colors, size, and more to better fit your site, then pricing starts at just $29.99 for a one time purchase. Click the "Customize" button above to learn more!