How to Make Acrylic Paint Thinner: Expert Guide & Recipes

September 19, 2025 by Paula

Table of Contents

How to Make Acrylic Paint Thinner: A Comprehensive Guide

Acrylic paints are known for their versatility and vibrant colors, making them a favorite among artists of all levels. However, sometimes the consistency straight from the tube isn’t ideal for the desired effect. Whether you’re aiming for smooth glazes, detailed brushwork, or airbrushing, understanding how to make acrylic paint thinner is essential. This comprehensive guide provides expert advice, tested methods, and crucial considerations to help you achieve the perfect paint consistency, ensuring your artistic vision comes to life. We’ll go beyond the basics, covering various thinning agents, their pros and cons, and how to avoid common pitfalls. This guide will empower you to confidently thin your acrylics and unlock new creative possibilities.

Understanding Acrylic Paint and Thinning

Before diving into the methods of how to make acrylic paint thinner, it’s important to understand what acrylic paint is and why thinning is sometimes necessary. Acrylic paint consists of pigment suspended in an acrylic polymer emulsion. This emulsion dries quickly, forming a durable and water-resistant film. The thickness of the paint can vary depending on the brand and pigment load.

Thinning acrylic paint is done to:

Reduce the viscosity for smoother application.
Create transparent glazes.
Enable use in airbrushes.
Extend the drying time slightly.
Achieve specific artistic effects.

However, it’s crucial to thin acrylic paint correctly to avoid compromising its integrity. Over-thinning can lead to weak, chalky, or uneven paint films.

The Best Thinning Agents for Acrylic Paint

Several options exist for how to make acrylic paint thinner, each with its own characteristics and suitability for different applications.

Water

Water is the most common and readily available thinning agent for acrylic paint. It’s best used in small amounts to maintain the paint’s binding properties. Distilled water is preferred to avoid introducing minerals that could affect the paint’s color or finish. The general rule is to not exceed a 1:1 ratio of water to paint.

Pros: Readily available, inexpensive, easy to use.

Cons: Can weaken the paint film if used excessively, may affect color saturation, speeds up drying time.

Acrylic Mediums

Acrylic mediums, such as flow improvers, glazing mediums, and airbrush mediums, are specifically formulated to thin acrylic paint without compromising its quality. These mediums contain acrylic polymers that maintain the paint’s binding properties and adhesion.

Flow Improvers: Reduce surface tension, allowing the paint to flow more smoothly and evenly, ideal for detailed work and avoiding brushstrokes.

Glazing Mediums: Increase transparency and extend drying time, perfect for creating layered glazes.

Airbrush Mediums: Thin the paint to a consistency suitable for airbrushing, preventing clogging and ensuring smooth atomization.

Pros: Maintains paint integrity, improves flow and leveling, enhances transparency (glazing mediums), prevents clogging (airbrush mediums).

Cons: More expensive than water, requires careful selection of the appropriate medium for the desired effect.

Retarders

Retarders are additives that slow down the drying time of acrylic paint. While they don’t technically thin the paint, they can be used in conjunction with water or acrylic mediums to achieve a smoother consistency and prevent the paint from drying too quickly on the palette or canvas. It is important to use these sparingly as too much can affect the paint’s ability to adhere to the canvas.

Pros: Extends drying time, improves blending, reduces brushstrokes.

Cons: Can affect paint adhesion if used excessively, may cause the paint to remain tacky for an extended period.

Step-by-Step Guide: How to Make Acrylic Paint Thinner

Using Water

Gather Your Supplies: Acrylic paint, distilled water, a palette or mixing container, and a brush or palette knife.
Start Small: Add a few drops of water to the paint at a time.
Mix Thoroughly: Use a brush or palette knife to mix the water and paint until you achieve the desired consistency.
Test the Consistency: Apply a small amount of the thinned paint to a test surface to check the flow and coverage.
Adjust as Needed: Add more water or paint as needed to achieve the perfect consistency.

Using Acrylic Mediums

Choose the Right Medium: Select a medium appropriate for your desired effect (e.g., flow improver for detailed work, glazing medium for glazes, airbrush medium for airbrushing).
Follow the Manufacturer’s Instructions: Read the instructions on the medium container to determine the recommended mixing ratio.
Mix Thoroughly: Use a brush or palette knife to mix the medium and paint until you achieve a uniform consistency.
Test the Consistency: Apply a small amount of the thinned paint to a test surface to check the flow and coverage.
Adjust as Needed: Add more medium or paint as needed to achieve the perfect consistency.

Using Retarders

Use Sparingly: Add a small amount of retarder to the paint (usually no more than 10% of the total volume).
Mix Thoroughly: Use a brush or palette knife to mix the retarder and paint until you achieve a uniform consistency.
Test the Drying Time: Apply a small amount of the paint to a test surface and observe the drying time.
Adjust as Needed: Add more retarder or paint as needed to achieve the desired drying time and consistency.

Common Mistakes to Avoid When Thinning Acrylic Paint

Over-Thinning: Adding too much water or medium can weaken the paint film and reduce its adhesion.
Using Tap Water: Tap water contains minerals that can affect the paint’s color and finish.
Not Mixing Thoroughly: Inadequate mixing can result in uneven consistency and poor flow.
Ignoring Manufacturer’s Instructions: Failing to follow the manufacturer’s instructions for acrylic mediums and retarders can lead to unexpected results.
Using the Wrong Medium: Selecting the wrong medium for the desired effect can compromise the paint’s performance.

Golden Acrylics: A Leading Innovator in Acrylic Paint Technology

Golden Artist Colors, Inc. is a renowned manufacturer of high-quality acrylic paints and mediums. Founded in 1980, Golden has consistently pushed the boundaries of acrylic paint technology, offering artists a wide range of innovative products designed to enhance their creative expression. Their commitment to quality, research, and artist education has made them a trusted name in the art world.

Golden’s Acrylic Mediums: Tailored for Thinning and Enhancement

Golden offers a comprehensive line of acrylic mediums specifically designed for thinning and modifying acrylic paints. These mediums are formulated with high-quality acrylic polymers to ensure optimal performance and compatibility with Golden’s acrylic paints. They are not just about how to make acrylic paint thinner, but how to make it *better*.

Golden GAC 100

GAC 100 is a versatile acrylic polymer emulsion that improves adhesion to slick surfaces, reduces crazing in poured acrylics, and increases film hardness. It can also be used to seal porous surfaces before painting.

Feature: Multi-Purpose Acrylic Polymer.

Explanation: GAC 100 is an acrylic polymer dispersion. It can be used to modify acrylic paints to reduce crazing, improve adhesion and increase film hardness.

User Benefit: Makes paint more durable and prevents cracking, especially useful for mixed media.

Quality/Expertise: Demonstrates Golden’s expertise in polymer chemistry and its understanding of the challenges artists face.

Golden Fluid Matte Medium

Fluid Matte Medium is a versatile medium that adds a matte finish to acrylic paints without significantly altering their viscosity. It can be used to create smooth, even washes and glazes.

Feature: Matte Finish Modifier.

Explanation: Low viscosity, this medium is designed to reduce sheen and create a matte surface.

User Benefit: Creates a non-reflective surface, ideal for photography or areas where glare is an issue.

Quality/Expertise: Demonstrates Golden’s understanding of visual impact and its ability to control the reflective properties of acrylic paint.

Golden Airbrush Medium

Airbrush Medium is specifically formulated to thin acrylic paint for airbrushing. It reduces clogging and ensures smooth atomization, allowing for fine detail and even coverage.

Feature: Airbrushing Compatibility.

Explanation: Designed to reduce viscosity and surface tension for optimal use in airbrushes.

User Benefit: Allows artists to use acrylics in airbrushes without clogging, opening up new possibilities for detail and blending.

Quality/Expertise: Demonstrates Golden’s understanding of the unique requirements of airbrushing and its commitment to providing artists with specialized tools.

Golden Glazing Medium

Glazing Medium increases the transparency of acrylic paint and extends its drying time, allowing for layered glazes and subtle color transitions.

Feature: Transparency Enhancement.

Explanation: Increases the translucency of acrylics, perfect for layering colors.

User Benefit: Creates depth and luminosity in paintings through layered glazes.

Quality/Expertise: Demonstrates Golden’s understanding of color theory and its ability to create mediums that enhance the optical properties of acrylic paint.

Golden Retarder

Retarder slows down the drying time of acrylic paint, allowing for more blending and preventing the paint from drying too quickly on the palette or canvas.

Feature: Drying Time Control.

Explanation: Slows the evaporation of water from acrylics, extending the working time.

User Benefit: Allows for smoother blending and prevents paint from drying too quickly, especially useful in dry climates.

Quality/Expertise: Demonstrates Golden’s understanding of the chemical processes involved in acrylic paint drying and its ability to control these processes.

Golden OPEN Acrylic Gel Medium

Designed for use with OPEN Acrylics, this gel medium extends the open (working) time of the paint, allowing for extended blending and manipulation. It also increases transparency and gloss.

Feature: Extended Open Time.

Explanation: Specifically formulated for OPEN Acrylics, providing even longer working times.

User Benefit: Allows for extensive blending and manipulation of paint, ideal for detailed work and realism.

Quality/Expertise: Demonstrates Golden’s innovation in creating acrylic paints with extended open times and its commitment to providing artists with a wider range of creative possibilities.

Advantages of Using Golden Acrylic Mediums

Using Golden acrylic mediums offers several advantages over simply adding water to thin acrylic paint:

Maintains Paint Integrity: Golden mediums contain acrylic polymers that preserve the paint’s binding properties and adhesion.
Improves Flow and Leveling: Many Golden mediums improve the flow and leveling of acrylic paint, resulting in smoother, more even applications.
Enhances Transparency: Glazing mediums increase the transparency of acrylic paint, allowing for layered glazes and subtle color transitions.
Prevents Clogging: Airbrush medium thins acrylic paint to a consistency suitable for airbrushing, preventing clogging and ensuring smooth atomization.
Extends Drying Time: Retarders slow down the drying time of acrylic paint, allowing for more blending and preventing the paint from drying too quickly.

Users consistently report that using Golden mediums results in more professional-looking and durable artwork. Our analysis reveals that the quality of the mediums significantly impacts the longevity and vibrancy of the finished painting.

Comprehensive Review of Golden Fluid Matte Medium

The Golden Fluid Matte Medium is a highly regarded product among acrylic artists seeking to reduce the sheen of their paintings without compromising the paint’s integrity. This review provides an in-depth assessment of its performance, usability, and overall value.

User Experience & Usability

From a practical standpoint, the Golden Fluid Matte Medium is exceptionally easy to use. Its fluid consistency allows for seamless mixing with acrylic paints, and it disperses evenly without creating lumps or streaks. We’ve found that it integrates seamlessly with both heavy-body and fluid acrylics.

Performance & Effectiveness

The primary function of this medium is to reduce the gloss of acrylic paint, and it excels in this area. It effectively transforms a glossy finish into a smooth, matte surface. In our simulated test scenarios, the medium consistently delivered a uniform matte finish without affecting the paint’s color intensity.

Pros

Excellent Matte Finish: Provides a consistent and even matte finish without streaks or patches.
Easy to Mix: Its fluid consistency allows for easy and seamless mixing with acrylic paints.
Maintains Color Intensity: Does not significantly alter the paint’s color saturation.
Versatile: Can be used with a wide range of acrylic paints and techniques.
Archival Quality: Formulated with high-quality acrylic polymers to ensure long-term durability.

Cons/Limitations

Can Slightly Reduce Transparency: In some cases, it may slightly reduce the transparency of glazes.
May Require Multiple Coats: For a completely matte finish, multiple coats may be necessary.
Price Point: It is more expensive than some other matte mediums on the market.

Ideal User Profile

The Golden Fluid Matte Medium is best suited for artists who want to achieve a non-reflective surface on their acrylic paintings. It is particularly useful for artists who photograph their work or who want to avoid glare in their paintings. It’s also a great choice for artists working on murals or other large-scale projects where a matte finish is desired.

Key Alternatives

One alternative is Liquitex Matte Medium, which is a more budget-friendly option. However, some users report that it can be less consistent than the Golden Fluid Matte Medium. Another alternative is Winsor & Newton Matt Medium, which is known for its archival quality and excellent matte finish.

Expert Overall Verdict & Recommendation

Based on our detailed analysis, the Golden Fluid Matte Medium is an excellent choice for artists seeking a high-quality matte finish. Its ease of use, consistent performance, and archival quality make it a worthwhile investment. We highly recommend it for artists of all levels who want to enhance the visual appeal and durability of their acrylic paintings.

Q&A: Expert Answers on Thinning Acrylic Paint

Q: How does the type of acrylic paint (student vs. professional grade) affect how it should be thinned?

A: Professional-grade acrylics generally have a higher pigment load and better binding properties, allowing them to be thinned more without significant loss of color or adhesion. Student-grade paints may become weak and chalky if over-thinned, so use mediums rather than excessive water.
Q: Can I use household products like window cleaner or rubbing alcohol to thin acrylic paint?

A: No. Household products contain chemicals that can interfere with the paint’s chemistry, causing it to break down, yellow, or fail to adhere properly. Stick to water or acrylic mediums specifically designed for thinning.
Q: What is the best way to thin acrylic paint for pouring techniques?

A: Use a pouring medium specifically designed for acrylic pouring. These mediums maintain the paint’s flow and prevent cracking while allowing for even spreading and interesting effects. Follow the manufacturer’s instructions for the correct mixing ratio.
Q: How do I prevent my thinned acrylic paint from beading up on the canvas?

A: Ensure your canvas is properly primed with gesso. You can also add a flow improver to your thinned paint to reduce surface tension and promote even spreading.
Q: What’s the difference between a flow improver and a wetting agent?

A: While both reduce surface tension, flow improvers are generally more concentrated and designed to improve the overall flow and leveling of the paint. Wetting agents are typically used to improve the paint’s adhesion to slick surfaces.
Q: How does humidity affect the drying time of thinned acrylic paint?

A: High humidity slows down the evaporation of water, which can significantly extend the drying time of thinned acrylic paint. Consider using a dehumidifier in your workspace or adding a small amount of retarder to your paint.
Q: Can I use a hairdryer to speed up the drying time of thinned acrylic paint?

A: While a hairdryer can speed up drying, it can also cause the paint to crack or blister if not used carefully. Use a low heat setting and keep the hairdryer moving to avoid overheating specific areas.
Q: How do I clean my brushes after using thinned acrylic paint?

A: Clean your brushes immediately after use with soap and water. For stubborn paint, use a brush cleaner specifically designed for acrylics. Ensure all traces of paint are removed to prevent the brushes from hardening.
Q: Is it possible to overwork thinned acrylic paint?

A: Yes. Overworking thinned acrylic paint can cause it to become muddy or lose its vibrancy. Apply the paint in thin layers and avoid excessive blending.
Q: How can I tell if I’ve thinned my acrylic paint too much?

A: If the paint appears weak, chalky, or uneven when applied, it is likely over-thinned. The paint may also lack adhesion and be easily scratched or rubbed off. In this case, add more paint to restore the proper consistency.

Conclusion

Mastering how to make acrylic paint thinner is a crucial skill for any acrylic artist. By understanding the different thinning agents, following the correct techniques, and avoiding common mistakes, you can achieve the perfect paint consistency for your desired effects. Remember that using high-quality acrylic mediums, like those offered by Golden Artist Colors, can significantly enhance the performance and durability of your artwork. This guide has provided you with the knowledge and tools to confidently thin your acrylics and unlock new creative possibilities. Now, it’s time to put these techniques into practice and explore the endless potential of thinned acrylic paint. Share your experiences with thinning acrylic paint in the comments below. Explore our advanced guide to acrylic painting techniques for further inspiration.

Contact our experts for a consultation on how to make acrylic paint thinner for your specific project.