Gravel Calculator

How much gravel do I need? The Gravel Calculator provides an estimate, based on your measurements.

To use the aggregate calculator, select the unit of measurement, either to metres, or feet, located in the top left corner and then enter your measurements into the Length and Width boxes directly below. The required Depth is determined by the product you wish to buy. The correct depth is important to ensure the calculation is as accurate as possible. (Please see the table below)

For Gravel & Chippings, the default depth is set to 50mm (1.97 inches) to ensure a gap free coverage, which is also suitable for Small Pebbles up to 20mm.

Pebbles up to 50mm, your required depth increases to 70mm (2.76 inches).

Cobbles up to 120mm require a depth of 100mm (3.94 inches) due to their larger, rounded shape.

Once your measurements have been entered with the appropriate depth for your preferred stone type, the gravel calculator provides the total m³ in kilograms, or tonnes, along with the equivalent quantity of 20kg poly bags or bulk bags for you to purchase from Stone Warehouse.

Not sure how much Rockery & Boulders are required? Please Contact Us for help or call 01629 636212.

Pebble Dashing is supplied in pallet quantities of industry standard 25kg poly bags, each covering approximately 2m² of wall.

If your project has any unique particular challenges to overcome, peculiarities of gradient, or a non-standard use, please Contact Us or call 01629 636212.


Gravel & Chippings, Pebbles up to 20mm

Pebbles up to 50mm

Cobbles up to 120mm

Recommended depth: 50mm (1.97 inches)

Recommended depth: 70mm (2.76 inches)

Recommended depth: 100mm (3.94 inches)

1 bag = 0.20mapprox.

1 bag = 0.167m2 approx.

 1 bag = 0.112m2 approx.

5 bags = 1mapprox.

6 bags = 1m2 approx.

9 bags = 1m2 approx.

1.00 Bulk Bags (800kg) = 10m2 approx.

 1.360 Bulk Bags (1088kg) = 10m2 approx.

1.00 Bulk Bags (800kg) = 5m2 approx.

Gravel Calculator

Total Volume (m3)
Bulk Bags

* This calculator is only intended as a rough guide to help you approximate the likely volume of gravel, slate or other aggregates needed for your project.

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