Sizing
How to Measure a Pillow Box
Most sizing disputes come from one ambiguity: whether a figure is internal or external. On a curved pack that difference is larger than it sounds, and this guide sets out how to measure and how to state what you have measured.
Internal or external, and which we work in
Internal dimensions describe the usable space inside the finished box. External dimensions describe the outside of the pack. The difference is the board thickness on each face, which is small on a 12pt stock and meaningful on an E-flute construction.
We work from the product. Send us the item, or its measured dimensions, and we derive the internal size from that and the external from the board. It removes the ambiguity entirely and it is why our quote form asks what goes in the box rather than what size box you want.
Measuring a curved pack correctly
-
Length — along the flat panel
Measure the long edge of the flat face, not around the curve. Measuring over the curve overstates the length by a surprising amount.
-
Width — between the tuck creases
The distance from one end crease to the other, again across the flat face rather than following the curve.
-
Depth — at the thickest point
With the box closed and a product inside, measure the maximum thickness. An empty pillow box measures thinner than a filled one.
-
Record the state
Note whether the figures are internal or external, and whether the box was empty or filled when you measured it.
Measuring your product
This is the more useful set of numbers, and the one we would rather have:
- The widest point in each axis, including caps, lids and applied labels
- The thickest point as the item actually rests, not as it is drawn
- Several samples if the product varies — hand-cut soap, baked goods, hand-poured candles
- The filled weight, which determines the board more directly than the size does
- Any part that stands proud and must not be pressed against the box face
Variable products need a different approach
A machine-made item has one dimension. A hand-cut soap bar, a baked cookie or a hand-poured candle has a range, and packaging sized to the average will not fit the top half of your production.
Size to the largest realistic item rather than the mean, and send us several samples from different batches so we can see the actual spread rather than guess at it. It is the single most useful thing a craft producer can do before ordering. The detail for one common case is on our soap packaging page.
Units and how to state them
| If you work in | State it as | Note |
|---|---|---|
| Inches | 5 × 3 × 1 in (external) | Decimal inches are easier than fractions on a dieline |
| Millimeters | 127 × 76 × 25 mm (internal) | The most precise option and our default |
| Centimeters | 12.7 × 7.6 × 2.5 cm | Fine, but convert to mm for anything under 3 cm |
| Mixed | Do not | Pick one unit and use it for all three figures |
Questions this raises
Do you work in internal or external dimensions?
We derive both from your product. Send the item or its measurements and we calculate the internal size needed and the external size that results from the board — which removes the ambiguity that causes most sizing problems.
Should I measure around the curve?
No. Measure across the flat panel. Following the curve overstates the length considerably and produces a box larger than you wanted.
My product varies in size. What do I send?
Several samples from different batches, and size to the largest realistic item rather than the average. Sizing to the mean means half your production will not fit.
Do you need the actual product?
It helps a great deal, particularly on small or awkward items where a nominal dimension and the real one differ. Where sending a sample is impractical, measured dimensions plus a photograph are usually enough.
How precise do the measurements need to be?
To the millimeter on anything under about four inches. Above that, half a millimeter of imprecision matters less than getting the depth and the filled weight right.