Sand Calculator
Enter your area and depth to instantly work out how much sand you need, in cubic metres, kilograms, tonnes, and standard bags.
Calculate How Much Sand You Need
Enter the length, width, and depth of your area, and choose a sand type, to see the volume and weight you’ll need to order.
Area & Sand Type
Measurements used to work out your sand requirement.
How it Works
Understanding the sand calculation
Calculate the Base Volume
We multiply length by width by depth to find the volume of sand your area requires, converting depth from centimetres to metres.
Add Your Wastage Allowance
Your chosen percentage is added on top of the base volume to cover compaction, spillage, and an uneven sub-base.
Apply the Sand’s Density
We multiply the total volume by the density of your chosen sand type to convert it into a weight in kilograms and tonnes.
Convert to Bags
Finally, we divide the total weight by 25kg and round up, giving you a practical number of standard bags to order.
Typical Sand Densities
A general overview of common sand types and what they’re typically used for.
| Sand Type | Approx. Density | Common Use |
|---|---|---|
| Sharp / Concreting Sand | ≈1,600 kg/m³ | Concrete mixes, block paving, mortar base |
| Building / Soft Sand | ≈1,450 kg/m³ | Bricklaying mortar, rendering, plastering |
| Kiln Dried Jointing Sand | ≈1,700 kg/m³ | Filling gaps between paving slabs and blocks |
| Play Sand | ≈1,602 kg/m³ | Sandpits and children’s play areas |
| Horticultural Sand | ≈1,500 kg/m³ | Soil improvement and lawn top-dressing |
Sand Calculator FAQ
Answers to the most frequently asked questions about calculating and ordering sand.
Multiply the length and width of the area by the depth of sand required to get the volume in cubic metres. Multiply that volume by the density of the sand type you’re using to get the weight, usually in kilograms or tonnes.
Sharp sand, also called concreting sand, has coarser grains and is used for concrete, mortar bases, and block paving. Building sand, or soft sand, is finer and softer, and is typically used for bricklaying mortar and rendering.
Yes. It’s common practice to add around 10% extra to account for compaction, uneven ground, and spillage during the job. This calculator includes a wastage allowance you can adjust to suit your project.
Standard builders’ bags of sand are usually sold in 25kg units, though bulk bags typically hold around 800kg to 850kg. Always check the exact weight on the specific product you’re buying, as it can vary between suppliers.