How to Measure The Jar Lids? Guide to Buying Canning Jar Lid

How to Measure The Jar Lids? Guide to Buying Canning Jar Lid

Canning jar lid might seem simple but for food business, understanding them is crucial. In our today article, we will explores their functionality, various types, bulk purchasing options, and answers common questions, empowering you to ensure safe and successful canning practices.

How Canning Lids Work

For food businesses utilizing canning processes, the humble canning jar lid plays a critical role in ensuring the safety and shelf life of your products. These lids operate on a simple yet ingenious principle: The two-piece system. Here are how it works:

  • Sealing Compound: The key component is a heat-activated sealing compound, typically silicone, located on the underside of the lid.
  • Heat Activation: During the canning process, heat softens this compound, allowing air to escape the jar and creating a crucial headspace vacuum.
  • Vacuum Seal: As the jar cools, the compound hardens, conforming precisely to the rim of the jar. This creates an airtight seal that effectively eliminates air and harmful microorganisms, preventing spoilage and ensuring the long-term integrity of your food products.

But are all lids equal? How canning jar lids many are there? How are they different? Explore in the next section.

Types of Jar Lids

There are different types of jar lids. They are caterogized by fuctions, sizes and materials composition. Here are some common types of jar lids that you should know.

Categorized By Function

The two most common types of jar lids here:

  • Lug Lids (also called Twist-Off Lids): Twist-off lids have raised rings or "lugs" on the inside edge allowing for a secure grip during the twisting motion. The jar itself will have multiple screw threads. 
  • Continuous Thread (CT) Lids (also called Screw Lids): This type of lid has a single continuous screw thread on the inside of the lid that is screwed onto a matching thread on the jar. Mason jars have CT lids.   

Categorized By Mouth Size

  • Regular Mouth Lids: Designed for jars with a standard-sized opening, which is typically around 2-3/8 inches in diameter. These are the most widely used size.
  • Wide Mouth Lids: These lids cater to jars with a wider opening, approximately 3 inches in diameter. This larger opening facilitates easier filling and spooning of products, particularly chunky items.

Categorized By Materials

  • Metal: The predominant material for both two-piece and one-piece lids, offering durability and heat resistance during processing.
  • Silicone: The primary sealing compound in two-piece lids, providing a flexible and airtight seal upon activation.
  • Plastisol: This material forms the lining in some one-piece lids, suitable for specific products and canning processes.

Lid Diameter

Here are common lid sizes:

  • Lug lids come in many sizes, the most common being: 63mm, 70mm, and 82mm.
  • CT lids come in many sizes, the most common being: 43mm, 70mm, 83mm, and 89mm.

Mason jar lids have 2 standard sizes:

  • Regular Mouth (60mm)
  • Wide Mouth (76mm)

How to Measure The Jar Lids

All you need to know is the lid's internal diameter. This is measured from the inside of the metal to the inside of the metal. As shown in the image below. It may not be precisely the same size, but it will only differ by one or two millimeters. Thus, it will let you know the size you need.

Where to Buy Canning Jar Lids in Bulk?

For businesses engaged in canning, buying canning jar lids in bulk is an excellent strategy to maximize cost-effectiveness. Canning jar lids can be readily obtained from various sources, including supermarkets, wholesale suppliers, and online retailers.

If your business operates in the North American market, Kimecopak stands out as a top-notch option for procuring canning jar lids with jars jugs bottles in bulk. As a leading wholesale packaging supplier, Kimecopak caters to a wide range of jar and lid products specifically designed for the North American market. Additionally, we offer customized logo services and provide valuable support for long-term partners, including:

  • Fixed pricing for 6 months
  • Instant savings of 5-7%
  • Free storage
  • Scheduled shipping

To learn more about Kimecopak's offerings and benefits for your business, please contact us via email at or visit Kimecopak Facebook Fanpage.

Considerations When Buying Canning Jar Lids

For food businesses engaged in canning, selecting the appropriate canning lids is paramount to ensuring product safety and long shelf life. Here are key considerations to guide your purchasing decisions:

Brand and Quality:

  • Prioritize Reputable Brands: Opt for established brands like Ball or Kerr, recognized for their consistent quality, reliable performance, and adherence to safety standards.
  • Safety First: Avoid off-brand or unknown brands, as these may not meet safety requirements or have a higher risk of failing during processing, potentially leading to spoilage and foodborne illness.
  • Beware of Counterfeits: Exercise caution when purchasing online, as counterfeit lids might be present. Stick to reputable retailers or directly purchase from the manufacturer's website.

Size and Compatibility:

  • Match Lids to Jars: Ensure the lids are compatible with the size and type of jars you utilize (regular mouth vs. wide mouth).
  • Bulk Purchases: When purchasing in bulk, double-check that all lids are the same size to prevent any mismatches.

Storage and Inspection:

  • Proper Storage: Store lids in a cool, dry environment away from direct sunlight to preserve the integrity of the sealing compound.
  • Inspect Before Use: Always meticulously inspect lids for any dents, rust, or other imperfections before incorporating them into your canning process. Compromised lids can jeopardize the seal and lead to spoilage.

Additional Considerations:

  • Price: While cost is a factor, prioritize quality over price when it comes to canning lids. Remember, the safety of your products is paramount.
  • Availability: Due to potential fluctuations in demand, canning lids can sometimes be in short supply. Consider purchasing in bulk when feasible or establishing a backup source in case of shortages.
  • Single-Use: Remember that canning lids are single-use and should not be reused.

By carefully considering these factors, food businesses can ensure they are procuring safe, high-quality canning lids that will effectively seal their products, ultimately contributing to the long-term safety and shelf life of their canned goods. But where to buy canning jar lids for the best price? Explore in the next section.

Frequent Asked Questions

Do Canning Lids Expire? How Long Will They Last?

Canning lids themselves don't technically expire, but the sealing compound's effectiveness can diminish over time. Ideally, use lids within 2-3 years of purchase for optimal performance. Store them in a cool, dry place away from direct sunlight to preserve the integrity of the compound.

Are Metal Canning Lids Reusable?

No, metal canning lids are single-use. The sealing compound forms a tight seal during processing, making it impossible to reuse it effectively for another canning session.

How to Tell if Lids Are New or Used?

New lids should have a smooth, flat sealing compound with no dents, scratches, or imperfections. Used lids will often have indentations or marks where the sealing compound has been compressed during a previous canning process.

Are Canning Lids Supposed to Pop?

No, canning lids should not pop during or after processing. A popped lid indicates a failed seal, which can lead to spoilage and potential foodborne illness. Discard any jars with popped lids and do not consume the contents.


Understanding canning jar lids is crucial for food businesses to ensure safe and high-quality canned products. By selecting the appropriate type, size, and source for your bulk purchases, and adhering to proper storage and inspection practices, you can optimize your canning operations and guarantee the long shelf life of your food items.

Back to blog

Leave a comment

Please note, comments need to be approved before they are published.

1 of 3

Discover our Top-Notch Summer Products, while it still last...



Share with our experts on your Products, Sizes, and Quantities, and let's cook up a tailored solution that screams YOUR style.

Your vision, our expertise – let's make it pop! Talk to us!