Glasslock Lid Sizes: Round, Square, and Rectangle Fit Guide
By Eco Friendly Glass Containers - Glasslock | Published: 2026-10-18
Category: Buying Guides
Learn how to match Glasslock replacement lids by model number, shape, and size. Use our decision rules to find the right fit every time.
Quick Answer
To find the right Glasslock replacement lid, check the model number on the bottom of your container—the first three digits after the letters indicate the lid size. Then choose the lid shape that matches your container: round, square, or rectangle.
Why Model Number Matters
Glasslock lids are not one-size-fits-all. Each container has a unique model number printed on the bottom, and the letters followed by the first three digits tell you exactly which lid size you need. Ignoring this can lead to buying a lid that doesn't seal properly.
The shape of the lid must also match the container's opening. A round lid won't fit a square container, even if the size digits are similar. Always confirm both the size and shape before ordering.
Shape and Size Trade-offs
Round lids are common for bowls and smaller containers, while square and rectangle lids suit meal-prep and storage dishes. Rectangle lids often provide more surface area for stacking, but square lids can be easier to align. There's no 'better' shape—only the one that matches your container.
If you have multiple containers, you may need to order different lid shapes. Keep a list of your container model numbers to simplify future replacements.
How to Choose the Right Lid Size
- Find the model number: Flip your Glasslock container upside down and locate the model number printed on the bottom. It will include letters followed by digits. Write down the full model number for every container you own.
- Read the first three digits: The first three digits after the letters indicate the lid size. Use these digits to match with the corresponding lid option. These digits are your key to compatibility—don't rely on memory.
- Match the shape: Select the lid shape that matches your container: round, square, or rectangle. The shape must align with the container's opening, not just the size digits. Double-check the shape before adding to cart to avoid a mismatch.
Glasslock Replacement Lid Options
- Round Lids: Round Lids: Lid sizes correspond to the model number located on the bottom of your glass container (letters followed by the first three digits). The color of the lid and/or silicone gasket may vary. Check the model number before ordering to ensure the round lid matches your container's diameter; color variations won't affect fit.
Round Lids - Square Lids: Square Lids: Lid sizes correspond to the model number located on the bottom of your glass container (letters followed by the first three digits). The color of the lid and/or silicone gasket may vary. Use the model number to confirm the square lid matches your container's dimensions, and be aware that lid color may differ from the original.
Square Lids - Rectangle Lids: Rectangle Lids: Lid sizes correspond to the model number located on the bottom of your glass container (letters followed by the first three digits). The color of the lid and/or silicone gasket may vary. For rectangle containers, the model number is essential to match both length and width; color variance is cosmetic and doesn't affect the seal.
Which Lid Shape Should You Choose?
Best for
- Round lids: best for bowls, soup containers, and round storage dishes.
- Square lids: best for compact meal-prep containers and uniform stacking.
- Rectangle lids: best for larger storage dishes and rectangular meal-prep trays.
Not for
- Round lids: not for square or rectangle containers—they won't seal.
- Square lids: not for round or rectangle containers—shape mismatch.
- Rectangle lids: not for square or round containers—dimensions won't align.
