FeaturedThe 48-inch line: 0.8 mm longer, several times the price

48 inches is 121.92 cm.

We had a box measured at the factory as 122 × 39 × 5 cm, 4.3 kg. 122 cm is 48.03 inches: 0.08 cm over the line. Same box, same address:

• Longest side 47.99 in: billed at 10 lb, normal price
• Longest side 48.00 in: billed at 10 lb, normal price
• Longest side 48.01 in: billed at 40 lb, several times the price

What jumps is the billable weight: over 48 inches on the longest side, the oversize surcharge applies, with a minimum billable weight. Every service on the rate sheet jumps together, so it is not one carrier misbehaving.

What to do

• Design products and packaging with the 48-inch (121.9 cm) line in mind and leave a margin: aim for 121 cm or less
• Measure accurately at the factory; rounding 121.95 up to 122 changes everything
• When a quote is suddenly absurd, check whether the longest side is just over the line