Can Liner Sizing Guide: How to Choose the Right Trash Bag
The wrong trash liner either slips into the can (wasting the whole bag) or blows out under load. Getting the size and thickness right is one of the easiest ways to cut waste and cost. Here's how to size can liners for your bins.
Versión en español: Guía de tamaños de bolsas de basura.
Match the liner to the can
A liner should overhang the rim by a few inches without pooling excess at the bottom. To size it: measure the can's circumference (for the liner's flat width) and its height plus a few inches for overhang. Round bins use a different fit than rectangular ones — check the recommended gallon range on the product.
Choose the right thickness
- High-density (HDPE) — thin, measured in microns. Best for light, dry waste like paper and restroom trash. Uses less material and costs less.
- Low-density (LLDPE) — stretchy, measured in mils. Best for heavy, wet or sharp waste (kitchens, warehouses, construction) because it resists punctures and tears.
Mils and microns are two units for the same thing, and neither predicts strength any more; mil vs gauge vs microns explains the manufacturer load ratings and the cost-per-pull math to use instead.
Common gallon ranges
Small restroom and office bins are typically 7–15 gallon; medium office/breakroom cans 20–30 gallon; large containers and outdoor bins 33–60 gallon. Buying the correct size for each bin avoids paying for oversized liners on small cans.
Browse can liners and trash bags in every gallon size and mil, or stock the full facility with commercial cleaning supplies. Not sure which mil you need? Ask us for a quote and we'll match liners to your bins.
Size and gauge sorted, the last spec is color, and it is a signal rather than a strength rating: black vs clear vs white can liners covers where each color belongs and the one case, red bags for regulated waste, where color is a rule.
FAQ
How do I know what size trash bag to buy?
Measure the can's circumference (for liner width) and its height plus a few inches for overhang, then match to the product's recommended gallon range. The liner should overhang the rim without pooling at the bottom.
What's the difference between high-density and low-density liners?
High-density (HDPE) liners are thin and best for light, dry waste; low-density (LLDPE) liners stretch and resist punctures, making them best for heavy, wet or sharp trash.
What thickness of trash bag do I need?
Light restroom/office waste needs thin high-density liners; heavy or sharp waste needs thicker low-density (mil-rated) liners. Matching thickness to the job avoids both blowouts and overspending.