Know exactly how much you need.
Free calculators for soil, compost, gravel and aggregate — giving you the answer in the bags and tonnes your local supplier actually sells.
A 120 × 80 × 30 cm raised bed, in 50-litre bags — with a settling allowance added.
Pick your project
Each tool switches between litres, bags, tonnes and cubic yards — and uses the right figures for your material and market.
Work out your soil in seconds
Enter your bed size below — no sign-up, no waiting. Switch to your region for local bag sizes.
Raised Bed Soil Calculator
Enter your bed size and we'll work out exactly how much soil to buy — in the bags your local supplier actually sells.
Advanced options
Bag volumes and settling vary by supplier. Always confirm quantities locally before you buy.
Built to get the number right
The right figures
Different materials weigh different amounts, and bag sizes differ by country. Our tools account for both — so your tonnage and bag count are right for what you actually buy.
We explain, not just calculate
Every tool comes with a plain guide: the depth to use, the waste to allow, the mistakes to avoid — the context a number alone can't give.
Honest by default
These are planning guides, and we say so. We tell you to round up, to check bag sizes with your supplier, and where costs can be trimmed.
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