Gravel Calculator
Not sure how much gravel you need? Enter the length, width and depth of the area and we'll calculate the estimated weight and pack quantities - instantly.
How it works
Three measurements are all you need
Length (m)
Measure the longest side of the area you want to cover, in metres.
Width (m)
Measure the shorter side in metres. For irregular shapes, use average dimensions.
Depth (mm)
Choose your desired depth in millimetres. 50mm is a good starting point for most projects.
Depth guide
How deep should you lay gravel?
Paths & Driveways
50-75mm
A deeper layer gives better stability underfoot and under vehicle weight. Compact in layers for best results.
Garden Borders
30-50mm
Enough to suppress weeds and look generous without being excessive. Lay over a weed membrane for best results.
Decorative Features
20–40mm
For pots, planters and ornamental beds a lighter dressing is all that's needed to create a neat, finished look.
Popular Decorative Aggregates
Common questions
Frequently asked questions
How much gravel do I need for my driveway?
For a driveway we recommend a depth of 50–75mm. Measure the length and width of the area in metres, enter them into the calculator above along with your chosen depth, and it will give you the estimated weight and pack quantities automatically.
How deep should gravel be laid?
For decorative garden borders 30–50mm is usually enough. For paths and lightly trafficked areas use 50mm. For driveways and areas that take vehicle weight, 75mm gives better stability and longevity.
How is gravel weight calculated?
We use a bulk density of 1700 kg per cubic metre, which is a reliable average across most decorative aggregates and gravels. The formula is: Volume (m³) = Length × Width × (Depth ÷ 1000), then Weight (kg) = Volume × 1700. The calculator does this instantly as you type.
What size bags does gravel come in?
We offer gravel in Single Mini Bags (approx. 20kg), packs of 7 Mini Bags (approx. 140kg), packs of 28 Mini Bags (approx. 560kg), Bulk Bags (approx. 800kg) and packs of 49 Mini Bags (approx. 980kg). The calculator shows how many of each size you would need for your project.
Do I need to use a gravel grid?
Not essential, but highly recommended - especially for driveways and paths. A gravel grid locks the gravel in place so it doesn't migrate underfoot or under vehicle tyres, reduces the depth of gravel needed, and gives a much cleaner, more stable surface over time. We offer two options: CORE Drive for driveways and areas that take vehicle weight, and CORE Path for pedestrian paths and lighter-use areas.
Do I need to lay gravel over a membrane?
For garden borders and decorative areas we strongly recommend laying a weed membrane underneath. It prevents weeds pushing through while still allowing drainage. For driveways, a geotextile membrane helps stabilise the sub-base and extend the life of the gravel surface.
Ready to order?
Browse our full range of decorative aggregates, gravels and chippings - available in multiple pack sizes to match exactly what your calculator says you need.
Shop Decorative Aggregates