Supply Chain View

Storage capacity calculator

This is a simple storage capacity calculator, similar to something I put together a few years ago for warehouse design projects. It takes a set of product dimensions, a list of possible storage modules (pallets, stillages, bins, shelves, etc.) of different sizes, and calculates the number of products that will fit in each module. Providing a desired quantity to store allows the calculator to suggest the best module.

I have not tested this to destruction, so I would appreciate any comments. Please see the notes on use below.

Credit should go to my colleague John Bradon who came up with the original algorithm.

Click here to open the Storage Capacity Calculator (in a new window).

(The user interface for this widget was developed using the Ext framework.)

Notes on use

The quick-start guide: enter the dimensions of a product, optionally a product weight, and the quantity you are aiming to store. Click on the Calculate button and see the module capacities calculated and the best module highlighted.

Data security

Any data that you enter in the calculator stays on your PC – no data is transmitted over the internet, no data comes to Supply Chain View.

Metric/US measure?

You will note that there are no units of measure when specifying dimensions. You can use any units of measure as long as you are consistent. The Lin Bin examples are in mm.

Weights and loading

If you omit product weights, then the calculator ignores loadings. If you specify a weight you should specify the loading limits of each module. The calculator will respect the loading limits when calculating the capacities.

Product dimension assumptions

The calculator assumes the product is a basic, regular cuboid, such as a cardboard carton. When I have more time I will test and upload an improved version of the calculator which deals with cylindrical products and products that stack (such as buckets).

Default module list

I have provided a few standard modules as a demonstration, but you can use the Delete Module and New Module buttons to remove these and add new modules. Double click on the names and dimensions of the modules to edit them. Remember to use the internal dimensions of the modules.

What quantity to store?

This deserves a quick explanatory post of its own. In brief, for small parts or slow-moving inventory this will be the maximum stock level you aim to hold. For faster movers the planned standard order quantity is a good number to start with (and once you have the capacity of a pallet that can feed back into the planned order quantity calculation…)

How do I do this for all my products?

Aha! This is just a little web widget, so the answer is, you can’t. It is possible to write this kind of logic in Excel for example, or Access, but you will need some help. I may at some point upgrade the calculator to allow people to upload a list of products and dimensions in a comma-delimited format (easy to export from Excel) and generate output in the same way – watch this space.

How it works

The capacity calculation takes into account all the possible orientations of a product (there are 6 for a cuboid carton) and finds the best fit. It also takes any free space and works out whether we can fit any more products in that space if we rotate them by 90 degrees. In this way it is a true calculation of capacity, something that a simple cubic volume calculation will overestimate (drastically if the product is large compared with the module).

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