Mailer boxes are sized from the inside out. The number you need is the interior cavity your product sits in, because that is what determines fit, and the exterior follows from the board thickness. Order by exterior dimensions and you will end up with a box your product does not fit into.
How to measure
- Length is the longer of the two edges of the opening.
- Width is the shorter edge of the opening.
- Depth is measured from the base up to the top edge of the wall.
- Write it as L x W x D in that order, always interior, always in the same unit.
Common mailer box sizes
| Interior size (inches) | Typically holds |
|---|---|
| 6 x 4 x 2 | Jewelry, small accessories, single cosmetics |
| 8 x 6 x 2 | Books, small electronics, flat goods |
| 9 x 6 x 3 | Skincare sets, candles, small multi-item orders |
| 10 x 8 x 3 | Subscription boxes, mid-size retail bundles |
| 12 x 9 x 4 | Apparel, shoes, larger subscription formats |
| 14 x 10 x 4 | Multi-garment orders, gift sets |
| 16 x 12 x 4 | Bulky apparel, homeware, larger kits |
These are the sizes buyers ask for most often. They are a starting point, not a constraint. Because the die is included, a size cut to your product costs no more in tooling than a common size does.
Clearance: how much air to leave
- Soft goods such as folded apparel: measure the stack when folded the way your packers will actually fold it, then add a little room so the lid closes without compressing.
- Rigid products going in with a paper insert: add the insert thickness on every face it touches.
- Multiple items: arrange them on a table in the layout you intend, measure the footprint of that arrangement, and size to it. This is faster and more accurate than adding item dimensions together.
- Fragile items: leave enough for cushioning on all six faces, and remember cushioning on the top matters as much as on the sides.
Depth, dimensional weight and cost
Carriers bill on the greater of actual weight and dimensional weight, and dimensional weight is calculated from the exterior volume. Depth is usually the dimension with the most wasted space, because packers pick a box that is tall enough for the worst case. Auditing depth across your top three shipping SKUs is often the quickest freight saving available. It also reduces the void fill you buy.
Ordering a custom size
The minimum order is 100 boxes. Pricing starts from about $0.48 per unit at bulk volumes and is confirmed on your written quote. The die, the plates, dieline design support, free US shipping and a digital proof are included. Production runs from about 7 business days, plus 2 to 5 for delivery, across rush (expedited production plus air freight, about 7 to 25% premium depending on the job), standard (air) and cost saver (sea) lanes, quoted per product.
Get a size quoted
Send your interior L x W x D and quantity to /quote/. For the style itself, see custom mailer boxes, and for how the die is drawn on a roll end tuck format, see die cut mailer dimensions.
