Gravel & Aggregate Calculator

How to use the Gravel & Aggregate Calculator

1. Select the aggregate type — gravel, MOT Type 1, sharp sand, topsoil, etc.
2. Enter the area dimensions and the required depth.
3. Add multiple areas if the project covers different sections.
4. Review the total tonnage and number of bulk bags or loose loads needed.

Why use this tool

• Uses built-in bulk density values for each material type, so you get tonnage not just volume.
• Multi-area support lets you calculate a driveway, paths, and borders in one session.
• Shows bulk bag counts (approximately 0.85 tonnes per bag) for ordering from the merchant.

Aggregates are sold by weight (tonnes) but you think about them in volume (how deep and how wide). The conversion depends on the bulk density of the specific material — MOT Type 1 is heavier per cubic metre than decorative pea gravel, for example. This calculator stores the correct bulk density for each common aggregate type and converts your area and depth into tonnes. It also converts to bulk bag counts, which is how most merchants sell to domestic customers. For larger quantities, ordering a loose tipper load is more economical — but you need to know the tonnage to get the right amount delivered.

Part of Builder Tools Calculators — construction tools for UK tradespeople.