Use a decision table
Record fit, protection allowance, finished outer volume, dimensional weight and threshold flags. Do not select on fill percentage alone.
Test the winning candidate
A calculation narrows the options. A physical pack test confirms assembly time, closure, movement and product protection.
Keep the comparison controlled
Use the same item quantity, protection standard, scale weight, unit system and carrier rule for every carton. Record the finished outer dimensions rather than comparing catalogue sizes.
- Current carton
- Smallest tested safe carton
- Operationally convenient alternative
- Same rule and packed weight for every result
Read the result beyond percentage savings
Volume reduction is useful, but the operational result may be a rounded billable-weight change, a threshold avoided or no carrier change at all. Keep packing speed, material use and damage performance alongside the calculated result.
Questions this guide should answer
What measurements should I compare?
Compare the closed outside dimensions, packed scale weight, dimensional weight, estimated billable weight and any relevant size thresholds.
Can a lower-volume carton cost the same to ship?
Yes. If both cartons round to the same billable value and cross no size threshold, the carrier pricing input may remain unchanged.