Why Mylar Bag Thickness Matters for Your Products?

Last updated: June 6, 2024.
Writen by :
Eric Lu
Marketing at Bagnpouch

Mylar bags are widely used for packaging and storing various products, from food items to electronics. These bags are known for their durability, flexibility, and excellent barrier properties. However, not all Mylar bags are created equal. One critical factor that can significantly impact the effectiveness of Mylar bags is their thickness. Choosing the right thickness is essential for ensuring optimal protection and preservation of your products.

In this blog, we will explore why Mylar bag thickness matters and how to select the best option for your needs.

What is the range of thicknesses available for Mylar bags?

Mylar bags are made from a type of polyester film known for its strength and resistance to moisture, light, and air. These bags are composed of multiple layers that provide excellent barrier properties, making them ideal for preserving and protecting various products.

The thickness of Mylar bags is measured in "mils," where one mil equals one-thousandth of an inch. This unit of measurement helps determine the bag's durability and protective qualities.

The standard thickness of Mylar bags typically ranges from 2 mils to 7.5 mils. The appropriate thickness for your product depends on the size of your packaging.

For smaller items, 3.5-4.5 mil bags are commonly used, while larger products may require 4.5-6.5 mil bags for optimal protection. It's important to note that Mylar bags below 4.5 mils may not provide sufficient barrier properties.

When storing food items for an extended period, opt for thicker bags, as they offer better insulation from external factors like moisture and air. Considering these thickness guidelines will help you select the most suitable Mylar bag for your specific application.

How does the Mylar bag thickness affect its protective qualities?

The thickness of Mylar bags plays a crucial role in determining the level of protection they provide against light, moisture, and oxygen.

Mylar Bags propertities 1

Here's how thickness impacts each of these factors:

Light protection: Thicker Mylar bags, especially those with an aluminum foil layer, offer superior protection against harmful UV rays. The thicker the bag, the less light can penetrate through, preventing product degradation caused by light exposure. This is particularly important for light-sensitive items like certain foods, pharmaceuticals, and electronics.

Moisture protection: Thicker Mylar bags provide a more robust barrier against moisture. They are less likely to allow water vapor to pass through, keeping the contents dry and free from humidity-related damage. This is crucial for products that are sensitive to moisture, such as dry goods, powders, and electronics.

Oxygen protection: he thickness of Mylar bags matters when it comes to preventing oxygen from entering the packaging. Thicker bags, particularly those with multiple layers and an aluminum foil component, offer better oxygen barrier properties. By minimizing oxygen exposure, thicker bags help prevent oxidation and extend the shelf life of the contents, which is essential for food products and other oxygen-sensitive items.

Comparing thin (2-3 mil) and thick (5-7.5 mil) Mylar bags reveals that thicker bags offer superior durability and barrier properties. Thin bags are more susceptible to punctures and tears, compromising the contents, while thicker bags are more resistant to damage and provide a stronger barrier against external elements.

Choosing the Right Thickness for Different Products

Selecting the appropriate Mylar bag thickness is essential for ensuring optimal protection and storage of your products.

fill mylar bags

Mylar Bag for Food Storage:

  • For dry goods like ground coffee, coffee beans, beef jerky, or granola, use bags with a thickness of at least 4.5 mils. This will provide adequate protection against moisture, oxygen, and light, maintaining the freshness and quality of the food items.
  • When storing grains or other products with sharp edges, opt for thicker bags, such as 5 mil or above, to prevent punctures and tears that could compromise the contents.
  • If you're packaging frozen foods, consider using thicker bags, like 7.5 mil, to provide extra protection against freezer burn and moisture.

Mylar Bag for Non-Food Items:

  • For electronics and components, use bags with a thickness of 3.5 mils or more to protect against static electricity and moisture damage.
  • When storing important documents or photographs, choose bags with a thickness of at least 4.5 mils to safeguard against moisture, light, and air exposure that could cause deterioration.
  • For items that require extra protection, such as collectibles or valuable memorabilia, consider using thicker bags, like 6.5 mil or above, to ensure long-term preservation.

Real-World Success: Mattina Coffee's Story

Mattina Coffee, a specialty coffee roaster, shared their experience with choosing the right Mylar bag thickness for their coffee products. They found that 4 mil pillow bags provided adequate protection for their ground coffee, while 5 mil gusset bags offered extra durability and puncture resistance for their whole beans, which have sharp edges that could potentially damage thinner bags. By selecting the appropriate thickness for each product, Mattina Coffee ensured optimal freshness and quality for their customers.

Long-Term vs. Short-Term Storage

The thickness requirements can vary depending on the intended storage duration.

For long-term storage, thicker Mylar bags (5 mils or more) are recommended. These bags provide superior durability and protection against moisture, oxygen, and light. Thicker bags are ideal for heavier items or products that need to be preserved for extended periods. For example, using thicker Mylar bags for storing grains, beef jerky, or frozen foods ensures they remain fresh and protected from environmental factors.

In contrast, thinner Mylar bags (3.5 to 4.5 mils) might be more appropriate for short-term storage or lightweight items. These small mylar bags are often more cost-effective and suitable for products with a shorter shelf life or those that will be consumed quickly. Situations where thinner Mylar bags are suitable include packaging samples, promotional items, or products like granola that are less sensitive to environmental factors.

By assessing your storage needs and the sensitivity of your products, you can select the appropriate Mylar bag thickness to ensure optimal durability and protection.

Practical Tips for Selecting Mylar Bag Thickness

When choosing the right Mylar bag thickness, consider several key factors to ensure optimal protection and performance:

  1. Product Weight and Size: Heavier items require thicker Mylar bags for better support and durability. For lightweight items, thinner bags may suffice, but always ensure they provide adequate protection.
  2. Sensitivity to External Elements: Products sensitive to moisture, oxygen, and light need thicker bags to maintain their quality. For example, food items like ground coffee, beef jerky, and frozen foods benefit from thicker bags to prevent spoilage.
  3. Handling and Transport Conditions: If your products will undergo rough handling or long-distance transport, opt for thicker Mylar bags. They are more resistant to punctures and tears, ensuring your items remain intact.

Tips for Testing Mylar Bag Performance

  1. Conduct a drop test: Fill the Mylar bag with your product and drop it from a specific height to see if it withstands the impact.
  2. Check for puncture resistance: Use a sharp object to test the bag's resistance to punctures.
  3. Perform a seal test: Seal the mylar pouch and observe if it maintains an airtight closure, especially under pressure.
  4. Assess barrier properties: Store the bag in different environmental conditions to test its ability to protect against moisture, light, and oxygen.

By considering these factors and testing methods, you can select the appropriate Mylar bag thickness to ensure your products remain safe and intact.


Selecting the right Mylar bag thickness is crucial for ensuring product safety, quality, and longevity. Consider factors such as product type, storage duration, and environmental sensitivity when making packaging choices.

Evaluate your current packaging solutions and consider whether your Mylar bag thickness meets your product requirements. Prioritizing appropriate thickness selection is a significant step towards ensuring product success and longevity in the market.


Are there any drawbacks to using thicker Mylar bags?

Thicker Mylar bags are more rigid and can be harder to seal and handle. They are also more expensive compared to thinner bags

What are the specific benefits of using thicker Mylar bags for long-term food storage?

Thicker Mylar bags offer superior insulation and durability, making them ideal for long-term storage by preventing punctures and maintaining an airtight seal, which helps in preserving the freshness and nutritional value of food.

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