Standard shipping box sizes

Common stock corrugated box sizes with metric conversions, volume and dimensional weight. Enter your product size to highlight the boxes it fits in.

Inside size (in)	Inside size (cm)	Volume	DIM weight (÷139)	Typical use
4 × 4 × 4 in	10.2 × 10.2 × 10.2 cm	0.04 cu ft	1 lb	Small parts, jewelry, samples
6 × 4 × 4 in	15.2 × 10.2 × 10.2 cm	0.06 cu ft	2 lb	Small accessories, cosmetics
6 × 6 × 4 in	15.2 × 15.2 × 10.2 cm	0.08 cu ft	2 lb	Candles, small gifts
6 × 6 × 6 in	15.2 × 15.2 × 15.2 cm	0.12 cu ft	3 lb	Mugs, small jars
8 × 6 × 4 in	20.3 × 15.2 × 10.2 cm	0.11 cu ft	3 lb	Books, phone accessories
8 × 6 × 6 in	20.3 × 15.2 × 15.2 cm	0.17 cu ft	4 lb	Small kitchenware
8 × 8 × 4 in	20.3 × 20.3 × 10.2 cm	0.15 cu ft	3 lb	Flat gifts, apparel
8 × 8 × 8 in	20.3 × 20.3 × 20.3 cm	0.30 cu ft	6 lb	Cube items, gift sets
9 × 6 × 3 in	22.9 × 15.2 × 7.6 cm	0.09 cu ft	3 lb	Folded apparel, books
10 × 6 × 4 in	25.4 × 15.2 × 10.2 cm	0.14 cu ft	3 lb	Shoes for kids, small electronics
10 × 8 × 4 in	25.4 × 20.3 × 10.2 cm	0.19 cu ft	4 lb	Books, boxed accessories
10 × 8 × 6 in	25.4 × 20.3 × 15.2 cm	0.28 cu ft	5 lb	Subscription boxes
10 × 10 × 6 in	25.4 × 25.4 × 15.2 cm	0.35 cu ft	7 lb	Gift sets, home decor
10 × 10 × 10 in	25.4 × 25.4 × 25.4 cm	0.58 cu ft	10 lb	Cube items, planters
12 × 6 × 6 in	30.5 × 15.2 × 15.2 cm	0.25 cu ft	5 lb	Bottles, long items
12 × 9 × 3 in	30.5 × 22.9 × 7.6 cm	0.19 cu ft	4 lb	Documents, apparel
12 × 9 × 6 in	30.5 × 22.9 × 15.2 cm	0.38 cu ft	7 lb	Apparel, small appliances
12 × 10 × 4 in	30.5 × 25.4 × 10.2 cm	0.28 cu ft	6 lb	Shoes, flat goods
12 × 10 × 8 in	30.5 × 25.4 × 20.3 cm	0.56 cu ft	10 lb	General shipping
12 × 12 × 6 in	30.5 × 30.5 × 15.2 cm	0.50 cu ft	9 lb	Kitchenware, home goods
12 × 12 × 8 in	30.5 × 30.5 × 20.3 cm	0.67 cu ft	11 lb	Home goods, multi-item orders
12 × 12 × 12 in	30.5 × 30.5 × 30.5 cm	1.00 cu ft	16 lb	General shipping, moving small items
14 × 10 × 6 in	35.6 × 25.4 × 15.2 cm	0.49 cu ft	9 lb	Adult shoes, small appliances
14 × 12 × 8 in	35.6 × 30.5 × 20.3 cm	0.78 cu ft	13 lb	Multi-item orders
14 × 14 × 6 in	35.6 × 35.6 × 15.2 cm	0.68 cu ft	12 lb	Flat home goods, trays
14 × 14 × 14 in	35.6 × 35.6 × 35.6 cm	1.59 cu ft	25 lb	Bulky light items
16 × 12 × 6 in	40.6 × 30.5 × 15.2 cm	0.67 cu ft	12 lb	Apparel, bedding
16 × 12 × 8 in	40.6 × 30.5 × 20.3 cm	0.89 cu ft	15 lb	Medium appliances
16 × 12 × 12 in	40.6 × 30.5 × 30.5 cm	1.33 cu ft	21 lb	Moving boxes, bulk goods
16 × 16 × 8 in	40.6 × 40.6 × 20.3 cm	1.19 cu ft	19 lb	Home decor, lamps
16 × 16 × 16 in	40.6 × 40.6 × 40.6 cm	2.37 cu ft	36 lb	Bulky items, pillows
18 × 12 × 6 in	45.7 × 30.5 × 15.2 cm	0.75 cu ft	13 lb	Long flat items
18 × 12 × 12 in	45.7 × 30.5 × 30.5 cm	1.50 cu ft	24 lb	Moving and storage
18 × 14 × 8 in	45.7 × 35.6 × 20.3 cm	1.17 cu ft	19 lb	Small electronics, printers
18 × 18 × 12 in	45.7 × 45.7 × 30.5 cm	2.25 cu ft	34 lb	Large home goods
18 × 18 × 18 in	45.7 × 45.7 × 45.7 cm	3.38 cu ft	50 lb	Moving, large light items
20 × 14 × 10 in	50.8 × 35.6 × 25.4 cm	1.62 cu ft	25 lb	Appliances, bulk orders
20 × 16 × 12 in	50.8 × 40.6 × 30.5 cm	2.22 cu ft	34 lb	Monitors, large appliances
20 × 20 × 10 in	50.8 × 50.8 × 25.4 cm	2.31 cu ft	35 lb	Wide flat items
20 × 20 × 20 in	50.8 × 50.8 × 50.8 cm	4.63 cu ft	67 lb	Large bulky items
24 × 12 × 12 in	61 × 30.5 × 30.5 cm	2.00 cu ft	31 lb	Long items, rolled goods
24 × 18 × 12 in	61 × 45.7 × 30.5 cm	3.00 cu ft	45 lb	Large appliances
24 × 18 × 18 in	61 × 45.7 × 45.7 cm	4.50 cu ft	65 lb	Large moving boxes
24 × 24 × 12 in	61 × 61 × 30.5 cm	4.00 cu ft	59 lb	Wide bulky items
24 × 24 × 24 in	61 × 61 × 61 cm	8.00 cu ft	113 lb	Extra-large bulky items

DIM weight is estimated from C-flute outside dimensions rounded up to the next inch. Availability of each size depends on the supplier.

USPS Priority Mail Flat Rate boxes

Flat Rate boxes ship at one price regardless of weight (up to 70 lb) within the US. Inside dimensions as published by USPS:

Box	Inside dimensions
Small Flat Rate Box	8 11/16 × 5 7/16 × 1 3/4 in
Medium Flat Rate Box (top-loading)	11 × 8 1/2 × 5 1/2 in
Medium Flat Rate Box (side-loading)	13 5/8 × 11 7/8 × 3 3/8 in
Large Flat Rate Box	12 × 12 × 5 1/2 in

USPS updates its packaging from time to time. Check usps.com for current sizes and prices.

Stock size or custom box?

Stock boxes are cheap per unit and ready to ship, which makes them right for low volumes and mixed orders. The trade-off is fit. If the nearest stock size leaves an inch or two of empty space on each side, you pay for that space in void fill and dimensional weight on every order.

Custom boxes are built to your exact inside dimensions. Minimum order quantities apply, but for a product you ship regularly, the savings on shipping and fill often cover the difference quickly, and you get the option of printing your brand on the box. Use the box size calculator to get the inside dimensions to quote.

Frequently asked questions

What is the most common shipping box size?

There's no single standard, but sizes such as 12 × 12 × 12, 12 × 10 × 8 and 16 × 12 × 12 inches are stocked by almost every packaging supplier and cover a wide range of products.

Are these inside or outside dimensions?

Inside dimensions. That's how stock boxes are sold. The outside is slightly larger because of the board thickness.

When should I use a custom box instead?

When your product leaves a lot of empty space in the nearest stock size, when you ship in high volume and dimensional weight is adding cost, or when you want printed branding on the box.