How to measure a box (the right way)
3 min read
Length × width × height, inside vs outside dimensions, and how to size a box to your item so it ships cheap and safe.
Length, width, height
Box dimensions are always written Length × Width × Height. Length is the longest side of the opening, width is the shorter side of the opening, and height (or depth) is the distance from the opening down to the bottom. Reading them in that order avoids ordering a box that's the right volume but the wrong shape.
Inside vs outside dimensions
Box sizes are quoted as inside dimensions, because that's the space your product actually has. Corrugated adds a small amount to the outside (roughly the board thickness), which matters when a box has to fit inside another box or a shelf. When in doubt, measure the inside.
Measuring your item
Measure your item's longest side, its width, and its height at the widest points, including anything that sticks out. Add clearance for padding: about half an inch for a snug fit, an inch if you'll use bubble wrap, and up to two inches all around for fragile items that need real cushioning.
Let the finder do the math
Instead of guessing, enter your item's size in Find My Box. It rotates the item for you, adds your chosen padding, and returns the tightest stock box that fits, along with the price and the estimated dimensional weight.
Find the right box in seconds
Enter your item and we'll return the tightest box that fits, with the price and shipping weight.
FAQ
Is it length or width first?
Length first: Length × Width × Height, where length and width are the two sides of the box opening and height is the depth.
Should I measure inside or outside the box?
Box sizes are inside dimensions. Measure the inside to know the usable space; the outside is slightly larger due to board thickness.
How much extra room should I leave?
About ½" for a snug fit, 1" if you'll add bubble wrap, and up to 2" on every side for fragile items that need cushioning.