How do I measure my product and choose the right board thickness for a custom rigid box?

What is the 3-step formula for calculating inside rigid tray dimensions?

When you request a quote on our rigid boxes page, enter the interior usable cavity of the base tray in Length × Width × Height (L × W × H) order. Follow these three steps depending on whether your item uses a direct fit or a die-cut foam insert

1. Step 1, Interior Length (L, left to right across the front presentation wall): Measure your product from left to right. For a direct fit (such as shoes, folded apparel, or a boxed candle), add 1/8 inch (3 mm). For an EVA or EPE foam insert, add 0.5 inches (12 mm) of solid foam on both the left and right walls (+1.0 inch total): L = Product Width + 1.0 in.
2. Step 2, Interior Width (W, front to back from front wall to back spine): Measure your product from front to back in the tray. Add 1/8 inch (3 mm) for a direct fit, or add 0.5 inches of foam on both the front and back walls (+1.0 inch total) for a foam insert: W = Product Length + 1.0 in.
3. Step 3, Interior Height (H, base floor to underside of closed lid): Measure the tallest standing or lying height of your item. For a direct fit, add 1/8 inch (3 mm) of head clearance so the lid closes flat. If you place a 0.25-inch foam base pad underneath a heavy glass bottle, add both the base pad (+0.25 in) and top head space (+0.125 in): H = Product Height + 0.375 in.
4. Multi-item gift kits (2 or more cavities): Leave at least 0.5 inches (12 mm) of solid foam bridge between adjacent product cutouts so the dividing wall never flexes when items are lifted out.

How much do 2 mm walls and EVA foam borders add to my box footprint?

Understanding how the structural grayboard core, paper wrap turn-ins, and foam insert fit together helps you plan both the interior presentation and your outer master shipping carton

1. Why EVA foam needs a 0.5-inch (12 mm) minimum border: Closed-cell EVA and EPE foam absorb drop shock by compressing slightly against the rigid tray wall. A foam rim narrower than 0.4 inches (10 mm) can buckle during parcel transit or pull away from the wall when the customer removes a snug glass bottle.
2. Finger notch cutouts (+0.5 insemicircle): For heavy bottles, candle jars, or tumblers recessed flush into EVA foam, our structural team adds two 0.5-inch semicircle thumb notches on opposite sides of the cutout or a satin lift ribbon underneath the bottle.
3. Inside-to-outside dimension math: On a Two-Piece Telescoping Box built with 2.0 mm (0.08 in) board, the base tray adds 4.0 mm (2 walls × 2.0 mm), the telescoping clearance gap adds 1.5 mm, and the overhanging lid adds another 4.0 mm, making the outside footprint roughly 9.5 to 10 mm (0.38 inches) larger than your inside L and W.

Should I choose 1.5 mm, 2.0 mm, 2.5 mm, or 3.0 mm chipboard for my rigid box?

Rigid setup box thickness is measured in millimeters (mm) or points (pt), where 1.0 mm equals roughly 40 pt (~600 gsm of compressed grayboard). Use this engineering chart to match your product weight and longest box dimension to the right chipboard core

What are standard rigid setup box sizes across luxury categories?

Every rigid setup box at CubitPack is built to order starting from just 50 units, with zero die or plate charges. Whether you are sizing custom perfume boxes, custom jewelry boxes, custom watch boxes, custom spirits boxes, or custom corporate gift boxes, use these benchmark interior tray dimensions as a reference

How do I verify my rigid box size and foam cutout before production?

Once you have your target inside tray dimensions, read our structural comparison, magnetic vs two-piece vs drawer vs shoulder neck rigid boxes, and our prepress guide, rigid box dieline, paper wrap, and V-grooving explained. Every order at CubitPack starts at 50 boxes with 10–14 business day standard turnaround (4–5 day rush available), free 2D dielines and 3D digital proofs before payment, and free US shipping.

1. Step 1: Measure your physical product (or full group of kit items) with digital calipers at its widest points, then add +1/8 inch (3 mm) per axis for a direct tray fit or +0.5 inches (12 mm) per wall (+1.0 inch total to Length and Width) for a die-cut EVA or EPE foam insert.
2. Step 2: Match your longest box dimension and total payload weight to the appropriate grayboard caliper: 1.5 mm (60 pt) for small boxes under 5.5 inches, 2.0 mm (80 pt) for medium boxes from 5.5 to 11 inches, or 2.5 to 3.0 mm (100 to 120 pt) for boxes over 11 inches or heavy glass bottles.
3. Step 3: Approve your free 2D vector dieline and interactive 3D proof showing the exact inside cavity, foam cutout bridges, finger notches, and outside master-carton dimensions before payment, or order our $50 sample kit (credited toward your box order) to feel our rigid board stocks in person.

What are the most common sizing and board mistakes on rigid boxes?

Check your rigid box dimensions against these five frequent specification errors before approving your dieline

1. Entering outside box measurements instead of usable inside tray L × W × H, which shrinks the interior cavity by 0.30 to 0.45 inches once the 2 mm walls and lid overhang are built.
2. Leaving less than 0.4 inches (10 mm) of EVA foam border between a heavy glass bottle and the rigid tray wall, allowing the thin foam rim to compress or tear in transit.
3. Forgetting to add the thickness of a bottom foam pad (+0.25 in) and top lid clearance (+0.125 in) to the interior Height (H), which stops a magnetic or telescoping lid from closing flat.
4. Specifying 1.5 mm (60 pt) board on a wide 13 × 10 inch corporate gift box, where 2.5 mm (100 pt) board is required to prevent the lid ceiling from bowing.
5. Designing a snug EVA foam bottle cutout without two 0.5-inch thumb notches or a satin lift ribbon, making it hard for the customer to lift the bottle out.

Packaging for this

Custom Rigid Boxes

Custom Perfume Boxes

Custom Jewelry Boxes

Custom Watch Boxes

Custom Spirits Boxes

Custom Corporate Gift Boxes

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