How To Make Your Acrylic Paint Runny (5 Easy Ways)

Acrylic paint that’s too thick can be very challenging to work with. Thinner acrylic paints have a more watercolor-like texture and work well in drip paintings, which you can use in different ways in your work. It’s easy to make your acrylic paint runny, so long as you’re careful not to overdo it. 

You can make your acrylic paint runny by combining the color with water or a pouring or thinning medium. You can also mix alcohol or acetone to thin your paints. Acrylic binders are also good at making your paint runny. Always track your materials and ratios to recreate the consistency later.

In this article, you’ll find everything you need to know to make your acrylic paints runny. Once you find a method you like, you can use it repeatedly to get the best consistency for your paintings.

Add Pouring Medium to the Acrylic Paints

If you’re considering making your paintings using the pouring technique, you’ll want to get a medium that lets you achieve the perfect consistency for the project. There are many acrylic brands out there that offer accompanying pouring mediums.

I recommend the Liquitex Professional Effects MediumOpens in a new tab. (available on, which comes in matte, gloss, or iridescent finishes. This medium makes the paint easily flow across your canvas. It’s perfect for creating poured paintings.

Overall, pouring mediums are incredibly easy to use. You just combine them with your acrylics, and you can start pouring. Most acrylic paint brands will have their own pouring medium formulas, which work best with their products.

Combine the Acrylic Paints With Water

Combining your acrylic paints with water is the easiest way to thin out your paints. Water breaks down the bindingOpens in a new tab. ingredient in the paint, causing it to appear more like watercolor. It also makes the paint have a matte finish.

Start by combining one part of water with three parts of acrylic paint. With this ratio, you’ll get thin paint that can still coat a canvas. Adding another part of the water will make it closer to a watercolor consistency. Having at least half of the mixture be water will create a paint wash.

It’s best to experiment with how much water you like in your acrylic paints. I recommend taking notes on how much water you use, so you can easily recreate your preferred paint texture again later.

Add an Acrylic Thinning Medium to the Paints

Acrylic thinning mediums are the preferred option of many artists for making acrylic paints runny. This option is popular because the medium doesn’t change the color of the paint. 

It also prevents the paint from peeling away from your canvas after drying. A thinning medium ensures that your paint remains glossy and prevents it from soaking into your canvas.

What Is an Acrylic Thinning Medium?

An acrylic thinning medium (or acrylic thinner) is a liquid you add to your paints to make them runnier. All this ingredient does is change the consistency of the pigment— it still has the glossy appearance of acrylics but will be much thinner.

Every thinning medium can be different, so you’ll want to make sure you follow the directions that come with the product for the best results. You’ll use less of a thinning medium compared to water.

Mix Alcohol or Acetone With the Acrylic Paints

Another way to make your acrylic paint runny is to use alcohol, which many artists use to prepare their paints for airbrushing. All you need to do is mix a one-to-one ratioOpens in a new tab. of rubbing alcohol and paint for great results.

You can also use acetone to thin your acrylic paints, and you’ll need to use a lot less acetone than alcohol. You’ll only want your paint mixture to consist of one-fourth of acetone compared to the color.

However, when using these ingredients in your paint, ensure you increase the ventilation in your room. They can release more pungent fumes, making you feel lightheaded or sick.

Can I Use Rubbing Alcohol To Thin Acrylic Paints?

You can use rubbing alcohol to thin your acrylic paints, as long as the alcohol isn’t more than 20%. I recommend adding small amounts to your paint at a time. You can make your color runnier by adding more, but it will dry faster.

So, add a few drops of rubbing, or isopropyl, alcohol to your paints. Combine them with a palette knife, and see what the consistency is like. If you like the results, you can start painting. But you can always add more alcohol to get a runnier texture with the paint.

Use an Acrylic Binder Medium With the Paints

Lastly, you can use an acrylic binder to thin the paint. It won’t change the finish or color of the paints and allows them to bond better with the surface you’re painting on. An acrylic binder is one of the main ingredients of acrylic paints, so it’s one of the best options for making a runnier paint.

Since it’s already a primary ingredient, the binder won’t break down the paint, so you don’t have to worry about the paint chipping later.

When Should You Thin Acrylic Paints?

You can make your paint look more like watercolors by making them runnier. Some artists prefer to paint with this texture or like how it looks better.

Depending on the material you use to thin your paints, you also can use them for poured paintings. These types of paintings require extremely liquid paints to get a unique effect. If the acrylics are too dense, they’ll hit a canvas and sit instead of running and dripping over the sides.

Thinning your paints also allows you to experiment with layering paints on your canvas and making your paint appear more matte or glossy, as per your preferences. Working with different consistencies of the same paint can open up a wide range of possibilities in your work. 

Final Words

To summarize, there are five easy ways to make your acrylic paint runny, including:

  • Using a pouring medium
  • Adding water to the paint
  • Combining the color with a thinning medium
  • Using alcohol or acetone
  • Adding more acrylic binding medium to the paint

WATCH – HOW TO: Acrylic Drip Painting DIYOpens in a new tab.

Sharrah Stevens – The Kinwoven Home
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Ines is a self-taught artist based in the UK. Originally from Caracas, she has dabbled in the world of arts and crafts in a diversity of ways participating in city intervention projects, sustainable practices’ open exhibitions, and her illustrations being featured in anniversary editions of literary magazines.

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