That's a great and very practical question! Figuring out the right size liner can be frustrating, but it's actually quite simple once you know what to measure. Here's a natural, step-by-step way to figure it out, just like I do for my own cans at home.
First, grab a tape measure. You'll need two key dimensions: the height and the girth (or width) of your can.
1. For the Height: Measure from the very bottom of the can's interior straight up to the top rim. Don't stop at the lid's hinge—measure to where the bag will fold over. This gives you the minimum *length* your liner needs.
2. For the Girth/Width: This is the most important step for a snug fit. Measure the circumference around the outside of the can at its widest point (usually near the top). If you don't have a flexible tape, use a string and then measure the string. This circumference number is the minimum *width* or *capacity* (like gallons) your bag should cover.
Now, grab a box of liners you're considering. Bag sizes are typically listed as "Gallons" (e.g., 30 gal, 55 gal). This refers to volume, but it's your best guide. Here’s the trick: Your liner's listed gallon size should be equal to or slightly LARGER than your trash can's gallon capacity. A 55-gallon bag for a 50-gallon can is perfect—it gives you extra material to fold over the rim.
A pro tip for a perfect fit: After placing the liner, pull it up and give it a gentle shake so it settles into the bottom corners. Then, roll the excess top material over the rim of the can. This creates a secure seal, keeps the bag from slipping in, and looks neat.
If your can is an odd shape (rectangular, square), just note its dimensions (Length x Width x Height) and look for bags marketed for that shape. Ultimately, buying a box of liners that are a bit too big is always better than dealing with ones that are too small and won't cover the rim. Happy lining