Most people asking this question are asking about one box when they need two. The retail box is sized to the product and the unboxing. The shipping carton is sized to a multiple of retail boxes and to the pallet. Quoting them together saves a round trip later.
The retail box
Put the headphones in their shipping position first: headband at its shortest setting, cups folded or rotated exactly as the insert will hold them. Then measure the widest span, the arc depth and the thickest cup to cup section, and add the wall thickness of whatever insert you are using. A moulded pulp or foam tray has real walls, and those walls are part of the internal dimension rather than a detail to add later.
Then add the accessory layer. A cable, a 3.5 mm adapter, a pouch and a quick start guide all need somewhere defined to sit. A lift out tray above the headphones is the tidiest answer and it costs internal depth, so decide it before the dieline is drawn rather than after.
How the answer changes by form factor
- Over ear. Headband span and arc depth lead. Expect the box to be taller than people guess because the arc does not flatten.
- On ear. Cup diameter and the folded stack depth lead, and the box is usually squarer.
- Wired in ear. The coiled cable is frequently wider than the buds. Coil it the way the packer will and size the well to that coil.
- True wireless. The charging case is the product envelope. A shallow tray or a small two piece rigid box sized to the case is the usual answer.
The shipping carton
Once the retail box is fixed, count how many go in a carton and lay them out on paper. Multiply the external retail box dimensions by the grid, add a little clearance and the board caliper, and check the result against a 48 x 40 in standard US pallet so the cartons do not overhang. Overhanging cartons are the ones that get crushed in transit, and they waste paid space on every shipment.
What about retail shelf depth?
If your buyer has given you a planogram, the external depth of the retail box is a hard constraint and everything else has to be designed around it. Get that number before the dieline. If the box hangs on a peg instead, the panel needs a hang feature and reinforcement behind it, which is covered on what a hang hole on packaging is.
Ordering
The minimum is 100 boxes, from about $0.48 per unit at bulk volumes, confirmed on your written quote. The die, the plates, design support, US shipping and a digital proof before printing are included, so quoting the retail box and the shipper together does not carry two tooling charges. Production is quoted per product in three lanes, rush (expedited production plus air freight), standard (air) and cost saver (sea), from about 7 business days, plus 2 to 5 for delivery, and specialty rigid or imported work can run up to about 12 weeks. We make at West Chicago and Guangzhou.
Send the headphones measured in the folded position, a list of the accessories and how many units go in a carton with your quote request. The full measuring routine, with insert options by form factor, is on how to size a headphone box.
