Box size finder
Measure the item, choose how much padding it needs, and see which of your boxes it fits, smallest first.
Item + padding → box
Smallest inner box
36 × 26 × 11 cm
item plus padding on every side
| Box | Size | Fit | Filled | Dim. weight at 5,000 cm³/kg |
|---|---|---|---|---|
| Medium | 40 × 30 × 20 | Fits 4 / 4 / 9 cm spare | 43% | 4.8 kg |
| Large | 50 × 40 × 30 | Fits 14 / 14 / 19 cm spare | 17% | 12 kg |
| Cube | 45 × 45 × 45 | Fits 9 / 19 / 34 cm spare | 11% | 18.23 kg |
| Shoebox | 35 × 25 × 15 | No too small by 1 / 1 cm | – | 2.63 kg |
| Long | 100 × 15 × 15 | No too small by 11 cm | – | 4.5 kg |
| Small | 22 × 16 × 10 | No too small by 14 / 10 / 1 cm | – | 0.7 kg |
Best fit: Medium, the smallest box that holds the item with its padding.
Finding the right box
Padding goes on both sides, so each of the item's sizes grows by twice the padding. That gives the smallest inside size a box can have. The finder then tries each of your boxes in every orientation, so a flat item can lie down or stand on its side, and lists the smallest box that fits first.
Minimum inside box = (L + 2p) × (W + 2p) × (H + 2p)
Example: a 30 × 20 × 5 cm item with 3 cm of padding needs at least 36 × 26 × 11 cm inside. A 40 × 30 × 20 cm box fits with room to spare, while a 35 × 25 × 15 cm shoebox is 1 cm too short in two directions.
Your boxes
The list starts with example sizes; replace them with the boxes you keep, using inside measurements. The outside of a corrugated box is a little bigger, so read the dimensional weight column as a slight underestimate. Your list stays in this browser for next time.
Questions
How much padding do I need?
It depends on how fragile the item is. Carriers publish packing guidance; as a rule of thumb, nothing should move when you shake the closed box.
Why is the smallest box best?
Less empty space means less filler, less movement in transit and, for bulky parcels, a lower dimensional weight.
Is my box list stored online?
No. It is saved in your browser's local storage on this device only. "Load example boxes" replaces it.