How to Thin Wood Stain? (Oil-based & Water-based)

If the wood stain is too thick, you must dilute it to make the application process easier. Thinning also helps to eliminate bumps and ridges in the finish. So, how to thin wood stain?

To thin water-based wood stains, use water or water-based paint thinner. To dilute oil-based stains, use mineral spirits. For lacquer stains, use lacquer thinner. 

Measure and add the right amount of thinner and stir the mixture until you have an even consistency. Then, test the mixture to see if it’s thinned.

Things To Know

You can dilute wood stain by using a ratio of 1:4 (1 part paint thinner and 4 parts stain). You can also dilute it by adding 2 tablespoons of paint thinner for every pint of stain. 

However, diluting it for large-scale tasks can be time-consuming because it will be difficult to dilute large amounts of stain and get the same color shade. 

If you will be using a sprayer to apply it, you must dilute it more. That’s because sprayers have a small nozzle that won’t apply (spray) thick coats. If you will be applying it using a brush, you don’t have to dilute the coating as much.

Also, thinning won’t affect the stain’s color as long as you thin it with the right amount of paint thinner. The color will only be affected if you over-thin it.

You should dilute wood stain for the following reasons:

  • To get a lighter flow so it’s easier to apply it. 
  • To help it dry faster. 
  • Makes it easier to spray it. 
  • To achieve a smooth and fine finish. 

How To Thin Wood Stain?

Diluting wood stain isn’t a difficult task, but it requires a bit of calculation to prevent you from over-thinning it.

You also need a few tools:

  • A paint bucket
  • Wood stain
  • A plastic funnel
  • Paint thinner
  • A paint mixer or turning stick

1. Open The Container

Open The Paint Container

Wood stains come in air-tight containers, so open the lid to access it. If it comes in a spray can, cut an opening at the top of the can to gain access to it. Without opening it, you can’t thin it.

2. Pour Out The Wood Stain

Pour Out The Wood Stain

Before doing this, you must clean the paint bucket. This is to remove paint residue, dust, and debris inside the bucket. To clean it, use a rag. 

Once the bucket is clean, pour the wood stain into it. Only pour the amount of stain you will be using.

3. Measure and Add The Paint Thinner

Measure and Add The Paint Thinner

Use water to dilute water-based stain, and mineral spirits to dilute oil-based stain.  To dilute lacquer or gel stain, use lacquer thinner. 

If you want to spray it, use a thinning ratio of 1:2 (1 part paint thinner, 2 parts wood stain). If you want to use a paintbrush, use a ratio of 1:4.

4. Stir The Mixture

Stir The Mixture

Next, stir the mixture using a turning stick or mixer to get an even flow and color. Using a paint mixer will be faster and produce better results. 

If you use a turning stick, don’t stir too fast or hard as it can cause air pockets to trap in the coating. Instead, move the turning stick in a figure of 8 motion. The turning stick must be long enough to reach the bottom of the bucket. This ensures that the wood stain at the bottom is also thinned. 

To dilute the lacquer stain, pour the thinning compound and stain from bucket to bucket. To do this, put the lacquer stain in one bucket and mineral spirits in another. Then, mix both of them by pouring from one bucket to another repeatedly. This limits the possibility of bubbles in the finish.

5. Test The Mixture

Test The Wood Stain

After you mix them for 10 minutes, test the mixture. If the diluted wood stain has an even flow and color, you don’t have to stir anymore. If the color shade is inconsistent, you must mix more and apply more stain to the mixture. 

Products To Use:

What Can You Use To Thin Wood Stain

You can use both natural and synthetic solvents, the choice depends on the type of wood stain you have, water-based or oil-based.


You can dilute water-based wood stain with water because this type uses water as its solvent. So, the more water you add, the thinner its flow gets.

However, you shouldn’t use water to thin oil-based or lacquer stains. That’s because they use oil as their solvent, and oil and water don’t mix.

Paint Thinner

Oil-based and lacquer wood stains can be diluted with paint thinner. But, to dilute the water-based stain, you must use water-based paint thinners. 

Paint thinners are gotten from a combination of turpentine, mineral spirits, acetone, xylene, naphtha, and toluene. These compounds are not compatible with water-based stains.

Mineral Spirits

You can use mineral spirits to dilute lacquer, oil-based, and gel stains only. Instead of mineral spirits, you can also use Varsol because it contains mineral spirits (although not in its pure form).


Acetone can thin it but isn’t the best choice. You should only use it if you have enough experience. If you don’t use it properly, you can ruin the coating instead of thinning it. That’s because acetone is natural paint remover and can separate the binder from the particles.

Does Thinning Change Its Color?

Thinning wood stain doesn’t make the color lighter but makes the paint flow or consistency lighter. The color isn’t affected when you dilute it with the right amount of paint thinner. The color shade will only get lighter or off if you over-thin it.

However, when you dilute it, the flow is affected. This means that thick coatings will become lighter or less thick. This is because when you thin, the amount of solvent increases. In other words, the solvent-to-stain ratio increases in favor of the solvent. This makes its flow lighter.

Tony Adams

Tony Adams

Woodworker, Interior and Exterior Painter, Flooring Specialist

Tony is a professional painter and an author of DIY Geeks. Tony has completed over 1,000 painting projects for his clients. It's safe to say he knows what he Is talking about.

Eral Kadrija

Eral Kadrija

Lead Editor, Home Renovator

Eral has a passion for home renovation and repair. Over the years, he has bought, renovated, and sold 7 old homes. Using his experience from different DIY projects he created DIY Geeks.

Leave a Comment