3D Box Packing Calculator — Find the Perfect Fit
Free interactive 3D packing tool. Enter your items' dimensions and instantly see the optimal box size, check if they fit a specific box, and preview how to arrange them efficiently. No signup required.
Enter items — I'll calculate the minimum box size
Extra margin for wrap and box walls
Add item
Interactive 3D Preview
Add items on the left and click "Calculate" to see the result
Optimization result
Add items on the left and click "Calculate" to see the result
Frequently Asked Questions
How does the 3D box packing calculator work?▾
The 3D box packing calculator uses a guillotine bin-packing algorithm to find the optimal box size for multiple items. You enter item dimensions, weight, and quantity. The algorithm tests all six rotation combinations, sorts items by footprint area, and stacks them horizontally. The result provides exact box dimensions in centimeters and an interactive 3D preview.
What is the difference between "Calculate box" and "Check your box" mode?▾
"Calculate box" determines the minimum box size required to fit your items. "Check your box" verifies if your items fit inside a specific container you already own. If items do not fit, the calculator displays the exact overflow in centimeters for length, width, and height, plus a fill-percentage indicator.
Is this packing calculator free to use?▾
The 3D packing calculator is completely free. We require no signup, account creation, or subscription. The tool contains no advertisements or paywalls. All box size calculations run directly in your browser, keeping your item data local to your device.
How accurate is the box size result?▾
The packing algorithm produces near-optimal dimensions for shipments containing up to 20 items. It calculates a physically feasible layout where items never overlap. By default, the calculator adds 3 cm of padding to each dimension for filler material and cardboard thickness. You can adjust this padding to 0 cm to get bare-minimum interior dimensions.
What does the padding / filler setting do?▾
The padding setting adds buffer space for bubble wrap, foam, or box walls. The default padding is 3 cm per dimension. In "Calculate box" mode, this value increases the final box size. In "Check your box" mode, it reduces the usable interior space. You can adjust padding from 0 to 30 cm in 0.5 cm increments.
Can I share my packing result with someone else?▾
You can share packing calculations using the "Share result" button. This generates a unique URL containing your item list, dimensions, mode selection, and padding settings. Anyone opening the link sees the exact same 3D arrangement and measurements instantly.
Does the calculator save my previous calculations?▾
The calculator automatically saves your last 8 sessions to a local history panel. You can restore or delete these entries at any time. This history remains entirely in your browser's local storage and clears when you delete your browser data. No server stores your shipping data.
What happens when my shipment is too heavy or too large?▾
The calculator flags shipments exceeding 30 kg actual weight or 36 volumetric weight. When a shipment crosses these carrier limits, the tool suggests splitting the items into two or more packages. It calculates separate dimensions and 3D previews for each sub-package.
What is dimensional weight and why does it matter for shipping costs?▾
Dimensional weight (or volumetric weight) is a pricing metric carriers use to charge for package volume rather than physical weight. Carriers calculate it as Length × Width × Height ÷ 5000 (in cm/kg) and bill the higher of the two values. The calculator displays both actual and dimensional weight so you can anticipate shipping costs.
Does the 3D packing tool work on mobile and tablet?▾
The 3D packing calculator works on all modern mobile and tablet browsers. The interface adapts from a single column on phones to three panels on desktop. The 3D visualization supports touch gestures: one-finger drag to rotate, two-finger pinch to zoom.
How many items can I pack at once?▾
The calculator supports up to 20 distinct item types per calculation. Each item type can have a quantity of 20, allowing up to 400 total pieces per box. Individual items can measure up to 200 cm per side and weigh up to 50 kg.
What if I don't know the weight of my items?▾
If you leave the weight field at 0, the calculator estimates it using a standard density of 0.3 kg per liter of volume. This estimate triggers weight warnings but does not change the physical box dimensions. Entering exact weights provides the most accurate shipping estimates.
Is my data private when using this calculator?▾
Your shipping data remains completely private. The calculator runs via JavaScript entirely in your browser. We send zero item dimensions or names to our servers. We use no analytics trackers on the packing inputs.
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