Foam insert calculator
Check how much foam surrounds a product in a box, and plan a two-piece cutout insert.
How it works
Foam works by compressing when the box is dropped, and it can only do that if there's enough of it. The thinnest wall of foam decides how well the product is protected, so the calculator reports the smallest gap on each axis.
A common design is two foam layers, each half the box height, with a cutout in each that's half the product's height. The product sits in the bottom layer and the top layer closes over it. Polyethylene foam is typical for heavy items; polyurethane is softer and suits light, delicate ones.
No box yet? Size one from the product with the box size calculator using the "Fragile" cushioning setting.
Results are estimates based on typical industry values. Confirm final specifications with your supplier or carrier.
Frequently asked questions
How thick should foam packaging be?
At least 1 inch (2.5 cm) on every side for most products, and 2 inches for fragile or heavy items.
Which foam is best for shipping?
Polyethylene foam for heavier and sharp-edged items; polyurethane foam for light, delicate products.
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