Box stacking calculator
Find how many boxes can safely stack on top of one another.
How it works
The bottom box in a stack carries every box above it. Divide the box's compression strength by a safety factor to get the load it can hold long term, then divide by the weight of each box.
Use a higher safety factor for long storage, humid or refrigerated warehouses, or when boxes overhang the pallet edge; each of these can cut real strength by a third or more. Don't know your box's strength? Estimate it with the box compression strength calculator. Remember the pallet stack also has to fit your racking and trailer height.
Results are estimates based on typical industry values. Confirm final specifications with your supplier or carrier.
Frequently asked questions
What safety factor should I use for stacking boxes?
3 for short, dry storage; 4 for typical warehouses; 5 to 6 for long storage, humid or cold conditions.
Does humidity weaken cardboard boxes?
Yes. At high humidity, corrugated board can lose a large share of its compression strength.
Related articles
- How many boxes fit on a pallet?
How to calculate boxes per pallet: boxes per layer, number of layers, height and weight limits, with examples on 48 × 40 and EUR pallets.
- Box compression strength and the McKee formula
What box compression strength (BCT) means, how the McKee formula estimates it from ECT and board caliper, and how to apply safety factors.
More box strength and weight tools
- Box compression strength calculator
Estimate how much top load a corrugated box can take, using the McKee formula.
- Packed box weight calculator
Add up everything in the box and see what you'll be billed for.