Resources
How to Size a Box, Carton or Bin Liner
Measure the inside of the container, choose gusseted or flat, and add overhang. Use the calculator for a starting size, then confirm it with a fit sample.
Calculator
Liner size calculator
Works for cartons, boxes, gaylords, totes and square bins. Results are rounded up and are a starting point, not a final specification.
Step by step
Measuring a gusseted liner
A gusseted liner has two folded side panels, so it opens into a rectangular base. It fits square cartons and bins with little wasted film.
- Width (W) = the inside length of the long side.
- Gusset (G) = the inside length of the short side.
- Length (L) = inside height + half the gusset (the film that folds under the base) + overhang or tie-off.
Example: a carton 600 × 400 × 300 mm with 150 mm overhang needs roughly 600 × 400 × 650 mm (W × G × L). In inches, a 24 × 16 × 12 in box with 6 in overhang needs roughly 24 × 16 × 26 in.
Australian and New Zealand suppliers often write the same liner as width × width + gusset, for example 600 × 650 + 400 mm. Check which order a supplier uses before comparing prices.
Step by step
Measuring a flat liner
A flat (lay-flat) liner has no gussets. It is simpler, and works for round containers such as octabins or when the liner is tied off.
- Width = half the inside perimeter (length + width), plus about 50 mm or 2 in so it isn't stretched tight.
- Length = inside height + half the short side + overhang or tie-off.
For a round container, use half the circumference (π × diameter ÷ 2) as the starting width.
Before you order
Things that change the size
Overfilling
If product mounds above the rim, add height so the liner still closes.
Closure method
Tied, taped, heat-sealed or folded closures each need a different amount of overhang.
Tapered containers
Measure at the widest point, usually the top inside rim.
Film thickness
Thicker film is stiffer and folds less easily, so allow a little extra size.
Fit sample
Not sure about the size?
Send your container dimensions and the liner you use today. We confirm the size with a fit sample before production.
Already have an existing liner? Send us a photo or sample.