Pick a carton that leaves two inches around the contents, wrap the item, fill every gap until nothing moves, seal top and bottom with the H pattern, then measure and weigh the finished box before buying anything. Six steps, all of them drawn from what UPS and FedEx publish, and the last one is where most of the money is won or lost.
Once the carton is sealed and measured, one description returns five live services.
Nothing here needs equipment beyond a tape gun, a marker and a scale. Every step exists because a carrier document asks for it.
There are two checks, one free and one formal, and most sellers only ever need the free one.
One rule sits outside both tests. Do not tape over the shipping label; FedEx states that to avoid scanning issues you should not apply tape over it. Secure the label edges instead, and put it flat on the largest face, which is where label placement picks the thread up.
The first two rows are the same garment, packed two ways, on the same lane on the same day. That pairing is the cleanest illustration of what your packing decision costs.
| Parcel as packed | Outer size | Weight | Cheapest rate returned |
|---|---|---|---|
| Cotton t-shirt in a poly mailer | 12 x 9 x 1 in | 0.7 lb | $8.86 |
| The same shirt in a carton | 10 x 8 x 4 in | 1 lb | $9.91 |
| Ceramic mug in a box | 6 x 5 x 5 in | 2 lb | $8.48 |
| Paperback book | 8 x 5 x 1.5 in | 1 lb | $9.91 |
Boxing the shirt added $1.05 for protection the shirt did not need. Read the other direction, the carton is cheap protection the moment the contents can crease, snap or scuff, and the mug row shows a genuinely fragile item costing less than either shirt because its box is small and dense. Size and density drive the number; the material inside barely registers.
Fragile contents change the calculus again, because the method grows a second carton. The double boxing page prices that step honestly, and the fragile guide covers the wrapping technique underneath it.
FedEx asks shippers to enclose an extra label, business card or letterhead carrying the sender and recipient details inside the package before sealing it. If the outer label is destroyed, that card is the only thing that gets the parcel home.
Shoe boxes and gift boxes count as chipboard, and FedEx states they must be packed into a corrugated outer box. Use them to present the product, never to carry it through a sorting hub.
Tape, fill and the carton itself all land on the scale, and together they add weight the item alone does not have. Buying a label off the item weight is the most common reason a correction shows up later.
Choose a carton with two inches of room around the contents, tape the bottom with the H pattern, wrap the item, fill every gap until the sealed box makes no sound when rotated, seal the top the same way, then measure all three outer dimensions and weigh the finished box before buying a label.
Two to three inches on every side. FedEx asks for a box large enough to allow 2 to 3 inches of cushioning on all six sides, and UPS asks for at least two inches of appropriate cushioning material against the corners, sides, top and bottom of the container.
A little. The same cotton t-shirt quoted $8.86 in a 12 by 9 by 1 inch poly mailer at 0.7 lb and $9.91 in a 10 by 8 by 4 inch carton at 1 lb, Newark, NJ 07102 to Atlanta, GA 30303, both on 2026-07-28. That is $1.05 for a rigid container.
Seal the box and rotate it slowly through every orientation, listening for movement. For products shipped in volume, UPS points to the International Safe Transit Association Test Procedure 3A, which subjects the packed carton to drops, vibration and compression.