How To Mix Paint For Spray Gun (8 Easy Steps To DIY)

Painting can be a daunting task, but with the right tools, you can get it done in a jiffy. Spray guns make painting so much quicker and easier, but it’s important to know how to mix paint for a spray gun.  

In this guide, you will learn the importance of mixing and thinning paint to get that perfect end result you want! 

What You’ll Need For Thinning And Mixing Paint 

When it comes to thinning your paint, you need to make sure you have everything you need to get the job done. Otherwise, you may thin the paint too much or not enough. Here’s what you need to get started:  

  • 1
    Obviously, you can’t thin the paint without the main ingredient. So, you’ll need to grab the paint you plan on using. 
  • 2
    Paint Strainer 
    You can use paint strainer bags or a reusable filter. They are designed with a fine mesh material to stain any impurities from your paint to give you a smooth and beautiful mixture. 
  • 3
    Water is essential for thinning your paint. You will need to add about ¼ cup of water to every gallon of paint you have to get the perfect consistency. 
  • 4
    Paint Sprayer 
    Before painting what you want to paint, you will want to use your paint sprayer to test the paint and ensure it’s thinned enough. 
  • 5
    Sprayer Tips 
    You will need a tip on the end of your paint sprayer. This tip determines the fan width of the spray and the flow rate.
  • 6
    Test Boards 
    Any wooden boards will do. You will use these to test the mixed paint with the spray gun to ensure the paint is the perfect consistency. 
  • 7
    Safety Goggles and mask 
    Safety measures should be of utmost importance. There is a risk of getting paint in your eyes when using a spray gun. Therefore, you should always wear goggles and a mask. 
  • 8
    You will strain your paint from its original container into another container. We recommend a clean 5-gallon bucket. 
  • 9
    Paint thinner 
    If you are mixing oil based paint, you will need a small amount of paint thinner instead of water to thin your paint. 

How To Mix Paint for Spray Gun (Thinning Paint For Sprayer)  

When it comes to thinning paint for a sprayer, it all boils down to the types of paint you are using. And, in some cases, you may not need to thin your paint at all. Follow the steps below to mix paint for a spray gun: 

Spray Gun

Step 1: Gather Your Materials 

First, gather everything you need to thin your paint which includes your sprayer, paint strainer, bucket, tips, water, and protective gear.  

Step 2: Choose The Paint 

Next, you will want to choose the type of paint you will be using. Keep in mind that latex paint can be thinned using just water [1]; however, oil-based paints will need to be thinned with a chemical paint thinner. If you already have paint, check to see what type of paint you have.  

Step 3: Put On Your Protective Gear 

Before you begin mixing the paint, make sure to put on your protective gear. A mask prevents you from inhaling potentially dangerous chemical fumes, whereas the goggles prevent you from getting paint in your eyes.  

Step 4: Strain The Paint 

Whether you are using latex, emulsion, enamel, lacquer, or oil based paint, you will want to strain the paint first! This is because most paints settle to the bottom of the container and form lumps that will inevitably clog your spray gun.  

To do this, attach your strainer or strainer bag to the empty bucket. Then, pour your paint slowly into the strainer [2]. Discard any pieces that remain in the filter.  

Step 5: Test The Paint 

Before you thin the paint, you should first test it to see if it even needs to be thinned. Put a tiny amount of the paint into your sprayer, attach the sprayer tip, and spray it on the test board. Examine the paint with the following tips in mind: 

  • Paint that is too thin will drip when it is applied to the test board. 
  • Paint that is too thick will have a texture kind of like that of an orange peel.  
  • Paint that is the right consistency will dry smooth and not drip.  

If your paint is the right consistency, then you can begin using it. However, if it is too thick, continue to the next step.  

Step 6: Thin the Paint 

Thinning your paint will be a little bit different depending on what type of paint you are using. To thin your paint, begin by pulling out a small amount of paint to thin at a time. There is no exact consistency, but you can get your paint close to perfect with the following guidelines: 

  • How to thin latex paint
    To thin latex paint or water based paint such as emulsion, the rule of thumb is to mix ¼ cup of water to every gallon of paint. 
  • How to thin oil based paint
    Oil based paints such as lacquer and enamel should be thinned using a paint thinner. You will want to add small gradual amounts of thinner to your paint until it reaches the desired consistency. Typically this amounts to 1 cup of thinner per gallon of paint.

Once you have added the water or thinner, mix your paint well with a paint stirrer.  

Keep in mind that there is no specific consistency when thinning paint. It is all a matter of how thick or thin you think the paint should be. 

Step 7: Test The Paint Again  

Once you think the paint is the right consistency, test it on a testing board again. If you still think the paint is too thin, repeat step 6 until you achieve the desired consistency. Remember, add water or thinner in small batches.  

Step 8: Begin Painting 

If the paint is at the perfect consistency, you can begin painting either indoors or outdoors. Start slowly with low pressure and spray the paint from left to right or top to bottom.

Do not start in the middle of your project, or you will have an uneven surface. If you are using the paint sprayer inside, be sure to familiarize yourself with how to use a paint prayer indoors for the perfect finish.  

Mix Paint for Spray Gun

Why Do You Have to Mix & Thin Before Spraying? 

Paint, especially latex paint, is so thick that it has to be thinned down before you can use it in a spray gun. Latex paint is thick because that's what makes it durable; however, if it's too thick, it won't flow through the spray gun nozzle the way that it should.

The result will be a huge mess that will ruin your equipment, floors, and whatever you are painting. Thus, the paint has to be properly thinned.  

What Happens If The Paint Is Too Thin? 

When thinning your paint, it is best to add small amounts of water or paint thinner at a time so that you don't accidentally make your paint too thin.

However, if you do make it too thin, you can remedy this problem by adding more paint to your mixture. Start by adding ½ cup of paint very slowly into the container you are using for your paint. Be sure to stir each time you add more paint until the paint thickens enough.  

Thinning Paint For Sprayer

Mixing Paint FAQs

Can you mix and thin Rust-Oleum paint for a spray gun? 

Yes, you can! Rust-Oleum can be thinned by mixing it with a thinner, like acetone, xylene, or mineral spirits (paint thinner).

To thin Rust-Oleum, mix 1 gallon of paint with 6.5 ounces of acetone or thinner to get the right paint consistency for your spray gun. Don’t forget to test the paint before using it. 

Can you use any paint in a spray gun? 

Yes, you can as long as you thin it properly before putting it in the spray gun. However, different sprayers work better with different paints.

For example, airless paint sprayers work best with oil-based paint, whereas HVLP paint sprayers work with both, but latex paint needs to be thinned. Additionally, Pneumatic paint sprayers work with oil-based enamel, acrylic, and latex paints.  

Can you thin acrylic paint with water? 

Yes, acrylic paint can be thinned with water. However, adding too much water can make the paint runny. To thin acrylic paint with water, you will want to add 30% water to the acrylic paint.


Spray guns can make painting quick and easy as long as you take the proper steps to thin the paint properly. Remember, to thin a small amount of paint at a time in case you add too much water or thinner. Refer to this guide whenever you plan to paint using a spray gun.