What Is 3D Bin Packing? How Cartonization Places Items in Boxes

Colorful rectangular items stacking inside a cubic bin like 3D bin packing

3D bin packing is the optimization problem of placing rectangular prism items into a rectangular prism container (a box). Academically it is NP-hard; production systems use heuristic engines for speed and determinism.

Problem definition

Input: container dimensions, item dimensions (each with quantity), legal rotations, weight limit. Output: (x, y, z) coordinates and rotation per item, or leftovers that cannot be placed.

Shipping cartonization is bin packing enriched with business rules, multiple boxes, and a rule engine.

Production requirements

Before marketing says “AI packing,” the engine must do the following:

Why volume math is not enough

∑(item volume) ≤ box volume is not sufficient in the real world. Items cannot always stack, voids form L-shapes, and a long edge can exceed a carton dimension.

Volume-only solutions constantly produce overrides at the pack bench.

WiCartonize engine

It uses extreme-point / free-space placement, multiple item-ordering strategies, and box-selection scoring. Results are visualized in Inspector with millimeter coordinates and rotation.

See engine and features for product capabilities.

Optimal solution or heuristic?

Optimal solutions are impractical for real-time fulfillment on most orders; consistent heuristics are the production standard.

How are soft goods (apparel) modeled?

Compressibility rules or separate profiles; the engine starts from rigid prism assumptions.