Most boxes that come out wrong are not drawn wrong. They are measured wrong: the product was measured in the wrong places, nothing was left for the wrapping, or the outside of the box was typed where the inside belonged. Here is how to get the numbers right the first time.
1. Decide which size you are typing
Every template on this site asks for the inside size: the space your product actually gets. The walls are added around it. That is the size you can check with the product in your hand, so it is the one worth typing.
The outside of the box is the inside plus two thicknesses of card on each measurement, and a little more where flaps overlap. If you are aiming at an outside limit, such as a shelf, a postal size band or a carton the box must fit into, work out the inside from it: take the outside limit, subtract twice your card thickness, then subtract a couple of millimetres more to be safe.
2. Measure at the widest points
- Length is the longest side when the product sits the way it will sit in the box. Width is the side across it. Height is straight up from the table, not along a sloping face.
- Measure the bulges, not the body. A candle jar is usually widest at the rim or the lid; a bottle at the shoulder; a soap bar at its rounded edge.
- Stand a ruler against a book or a box corner to read heights. Measuring height with a loose tape measure is where most millimetres go missing.
- For several items in one box, lay them out exactly as they will sit and measure the whole group.
3. Add room, but not too much
A box that is the exact size of the product will not close: there is no room for the product to go in, for card that is not perfectly folded, or for the wrapping. A box with too much room lets the product rattle and makes the gift look smaller than it is.
- Rigid things (jars, boxes, bars, jewellery cards): add 2 to 4 mm to each measurement.
- Soft things (clothing, fabric, sweets in a bag): add little or nothing; they squash to fit.
- Wrapped things: add the thickness of the wrapping on both sides. Two layers of tissue paper are thin; bubble wrap is often several millimetres a layer, so measure it folded the way you will use it.
- Items with a lid or a wick: add height for anything that sticks up. An untrimmed candle wick needs a few millimetres above the jar.
4. Tell the template your card thickness
Card has thickness, and that thickness turns corners. If a lid is cut to exactly the size of the base, card on card stops it sliding on. The templates here allow for this: set the material thickness in the maker to the card you are really using and the lids, tucks and slots are adjusted for it.
Measure the card itself. Callipers are best; a stack of ten sheets measured with a ruler and divided by ten also works. As a rough guide, printer paper is about 0.1 mm, thin card about 0.3 mm, cereal-box card about 0.5 mm, and corrugated board 3 mm or more. The guide to choosing card covers what each one is good for.
5. Fold a paper test before anything else
This is the step that saves money. Before you print on good card, or order anything:
- Print the template on ordinary paper at 100% (actual size).
- Cut it out roughly and fold it. Tape is fine; this one is going in the bin.
- Put the real product in it, with its wrapping.
- Change the size by what you saw, then print again.
Paper is thinner than card, so the paper test runs very slightly roomy. If the product is snug in paper, add a millimetre before printing on thick card.
6. Pick the shape after you have the size
The size often decides the shape for you:
- Flat and wide, such as a scarf, a print or a tart: Shallow box or Mailer box.
- Tall and narrow, such as a bottle or a tube: Card box, Round box or Paper bag.
- A gift that should open in two pieces: Box with lid.
- Several small things that must not touch: Box with dividers or a Tray insert inside a larger box.
If something will be posted, check your carrier's size bands before you settle the size. They differ by country and by carrier and change from time to time, so read the current table on their site. A box a few millimetres smaller can fall into a cheaper band.
A quick checklist
- Inside size, measured at the widest points.
- 2 to 4 mm added for rigid items, plus any wrapping.
- Card thickness set in the maker to the card you measured.
- A paper test folded with the real product inside.