Box Dieline Designer
Enter your inside box dimensions and instantly see the flat cutting layout and how it folds into a finished shipping box. Free tool from Prime Carton, corrugated box manufacturer in Scarborough, Ontario.
Your box size (inside dimensions)
Length is the longer side of the opening, width the shorter, depth the inside height. Reference layout for planning and artwork; production dielines are fine-tuned by our team for your board grade and print.
Like this box? Get it priced.
Send us these exact dimensions and we will quote your quantity within one business day. Made in Scarborough, shipped across the GTA.
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Tell us where to reach you and your download starts right away. We will also keep your dieline on file in case you want it quoted.
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About box dielines
What is a box dieline?
A dieline is the flat blueprint of a box before it is cut, scored, and folded. It shows every cut line, fold line, panel, flap, and the glue tab exactly as they sit on a flat sheet of corrugated board. Packaging designers use dielines to lay out print artwork, and manufacturers use them to set up cutting dies. This free dieline generator produces the layout for a Regular Slotted Container (RSC), the standard shipping box style used for the vast majority of e‑commerce and industrial packaging.
How to use this dieline generator
Enter the inside length, width, and depth of the box you need, in inches or millimetres, and choose a board type. The tool instantly draws the flat cutting layout with every panel dimension, calculates the blank size and board usage, and shows a 3D preview you can fold and rotate. Download the layout as a PDF to share with your team or send to us for a production quote.
Why are the panel sizes bigger than my box dimensions?
Corrugated board has thickness, and every fold consumes some of it. A 12 inch inside panel is scored slightly wider than 12 inches so that after folding, the inside of the box measures true. This is called a fold or scoring allowance. Our generator applies a standard allowance for each board grade, which is why a 12 x 9 x 6 box shows panels of roughly 12.12 and 9.12 inches. Production dielines fine-tune these allowances for the exact board and machine.
Can I use this dieline for production?
Treat it as a reference layout for planning, artwork positioning, and quoting. Production dielines are adjusted for board grade, print method, and machine allowances. When you order from Prime Carton, our team produces the final manufacturing dieline for your exact specification.
What is the difference between inside and outside dimensions?
Box sizes are always quoted as inside dimensions, length x width x depth, because that is the space your product occupies. The outside is larger by roughly two board thicknesses in each direction, which matters when calculating pallet counts and dimensional shipping weight.
What box sizes can you manufacture?
We manufacture custom RSC boxes in 32 ECT kraft corrugated across hundreds of sizes, with made‑to‑order runs starting at 500 boxes and a Ready to Ship range available for same‑day pickup in Scarborough or 1 to 2 day delivery across the GTA.
What is a blank size?
The blank is the flat rectangle of board a single box is cut from. Blank size drives board cost, which is why two boxes with the same volume can have different prices. The generator shows your blank size and board area for every size you try.
Is this tool really free?
Yes. Design as many boxes as you like with no account. We ask for contact details only when you download a PDF, so we can keep your dieline on file in case you want the box quoted.