Practical guide
Use dimensional weight as a separate carton comparison
A carton can fit while its volume still affects a shipping comparison. Carton Fit Desk keeps dimensional weight, chargeable weight, and unit cost visible as separate inputs.
Enter the divisor with its units
Candidate carton dimensions are entered in millimetres, then converted to cubic centimetres for dimensional weight. Use the divisor supplied for the carrier or contract lane and keep its date and units in your purchasing notes.
dimensional kg = carton volume in cm3 / entered divisor in cm3 per kg
Compare the larger weight
The engine reports the larger of the entered product weight and calculated dimensional weight for each candidate. This is a comparison field, not a live rate or a shipping quote.
chargeable comparison kg = max(product kg, dimensional kg)
The default product weight is 1.8 kg; each carton row is evaluated against that value and its own entered divisor.
Use the result to guide a sample check
After filtering to cartons that fit, compare unit cost, available quantity, volume, and the chargeable comparison. Recheck the chosen inner size and divisor whenever the product, packaging, or carrier lane changes.
- Keep one product per carton in this worksheet.
- Treat a no-fit result as a measurement prompt.
- Replace illustrative costs with dated purchase assumptions.
Check your own scenario
Replace the illustrative inputs with measured values and dated specifications.
Open Carton Fit DeskMethod and references
Read the full calculation method and its limits
Method and examples reviewed 2026-09-30. Examples are illustrative; input values and specifications are not independently verified.