Need to work out how much material the project requires?
Use the Kelkay aggregate calculator for free to determine what you need.


Measure the length and width of the area to cover.

Select the type of product from the dropdown menu, and input your measurements. Please note that for calculating gravel coverage, we recommend a minimum laying depth of 35mm for sufficient coverage.

Click calculate to estimate the ideal aggregate volume.



To understand how much gravel you require, you simply need to work out the area coverage by multiplying the length by the width and then the depth. The depth is least important as we typically recommend a depth of 30-50mm coverage for all decorative aggregates, chippings, gravel, slates and pebbles. This information is already inputted into our handy calculator.

To use the Kelkay aggregate calculator, input the length and width of the area you want to cover. We’ve already input the depth – recommended at 30-50mm coverage for all our decorative aggregates. If you want to change the depth to suit your space, change it in the calculator before submission.

Using a tape measure, measure around the edge of your garden. Start by measuring the longest length and width of the space. If you have any irregular or curved areas, measure each separately. Add your measurements to the calculator, and it will work out square metreage and how much material you need to cover the space.

For decorative aggregates, chippings, gravel, slates, and pebbles, we recommend a depth of 35mm. The depth is already set in the calculator, but you can change it to suit individual projects.

Yes, it can. While the calculator tool is an approximate guide, it will give you a reliable estimate of the volume of material to order.

We have a range of decorative aggregates ideal for gardens, driveways, paths and ponds. Select the right product by browsing pebbles, slate, chippings and rockery today.

Our calculator can be used for most gravel and aggregates featured on our website. Use the drop-down menu to select what product type you are interested in.

We hope our aggregate calculator is useful and helps you to work out how much product is needed for your project. However, if you have any further queries, please contact our customer service team who are happy to help.

As a trade business, we don’t sell directly to the public. You can find our products in garden centres and retailers around the UK. Use our find a stockist tool to locate your nearest retailer.


If you have any questions about our aggregate calculator or would like some help, please contact our customer service team who are always happy to help.

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