Calculate mulch, soil or gravel volume
Enter the area and depth you need to cover. Add an allowance and a bag size if you know it.
No account needed · Your entries stay in your browser
Use the supplier’s material and depth
Measure the area to be covered and enter the depth required for your selected material and use. Enter a known area, or use length × width for a rectangle. Volume is area × depth after converting centimetres to metres. The garden map tool can send an irregular measured area directly to this calculator.
This is a volume calculation for mulch, soil or gravel. It does not design a patio foundation, recommend a layer depth or convert to tonnes: density, moisture, compaction and supplier conventions differ.
Make the allowance explicit
The optional percentage is your allowance for an uneven surface, losses or settlement. Zero means no allowance. There is no automatic material-specific waste assumption. Confirm the suitable allowance with the supplier or installer.
If buying bags, use a labelled volume in litres. Do not treat a bag sold only by weight as a known volume. The tool rounds up to whole bags, so the purchased volume can exceed the modelled need.
Plan delivery and access
Check where the supplier will deliver and who will take the material to the garden. Material quantity and delivery scope are different questions. Use the access guide before requesting an installation quote.
Your measurements and selected assumptions stay in your browser. The result is a planning estimate; it does not represent a supplier quote or availability.
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