How Much Topsoil Do I Need?
Enter your area dimensions and required depth. We'll estimate volume, litres, weight, and bulk bags. Supplier bag sizes and soil density vary, so confirm the final delivered price before ordering.
Calculate your topsoil volume
Tips for measuring accurately
- 1.For irregular shapes, divide the area into rectangles, calculate each separately, then add them together.
- 2.No tape measure? Pace it out. One normal walking stride is roughly 0.75 metres. Count your strides and multiply by 0.75.
- 3.Depth matters most. A small error in depth across a large area adds up fast — measure in multiple spots and use the average.
- 4.Check vehicle access before ordering. Bulk bags are delivered by lorry and need a firm, level surface close to the drop-off point. Most suppliers need at least 3 metres of clear width.
How to Measure Your Area
Accurate measurements save you money. Ordering too little means a second delivery charge; ordering too much means wasted topsoil. Here's how to measure any area.
1. Rectangular areas
Measure the length and width in metres, then multiply them together. A bed that's 6m long and 3m wide = 18m².
2. L-shaped or irregular areas
Split the area into two or more rectangles. Measure and calculate each one separately, then add the totals together. For example, an L-shaped garden might be a 10m × 6m rectangle plus a 4m × 3m rectangle = 72m².
3. Circular areas
Measure the diameter (the widest point across), halve it to get the radius, then use the formula: π × radius². A circular bed with a 4m diameter has a 2m radius: 3.14 × 4 = 12.6m².
No tape measure? Pace it out. One normal walking stride is roughly 0.75 metres. Count your strides along each edge and multiply by 0.75 to convert to metres. It won't be perfect, but it's close enough for an initial estimate.
What Changes the Delivered Price?
The calculator estimates how much topsoil you need. Delivered price has to be confirmed with the supplier because heavy topsoil orders depend on product type, quantity, delivery format, postcode, selected date, access, and order size.
Product type
Screened, blended, enriched
Screened topsoil, sandy loam, enriched garden soil, and BS3882-labelled products are not the same. Compare the product page against your use case.
Delivery format
Bag, loose load, pallet
Bulk bags, loose loads, pallets, crane or HIAB drops, tail-lift deliveries, and tipper vehicles all have different access needs.
Access and date
Postcode, slot, driveway
Narrow roads, slopes, parked cars, gravel drives, kerbs, and overhead cables can affect what the supplier can deliver.
Use the calculator for quantity planning, then use the supplier website to check live postcode availability, delivery format, selected date, access requirements, and total delivered price.
Understanding Depth Requirements
The amount of topsoil you need depends on the project. Here are recommended depths for common garden uses.
| Use | Recommended Depth | Notes |
|---|---|---|
| New lawn (turf) | 100–150mm | Minimum 100mm for healthy root establishment |
| New lawn (seed) | 150–200mm | Slightly deeper as seed needs more root depth |
| Flower beds & borders | 200–300mm | Deeper for shrubs and perennials |
| Raised beds | 300–450mm | Fill entire bed; mix with compost for veg growing |
| Levelling / top dressing | 25–50mm | Thin layer to even out dips in existing lawn |
| Vegetable garden | 300–450mm | Root veg needs the deepest topsoil layer |
Topsoil: Weight and Volume
Weight per m³
≈ 1.3 tonnes
Varies with moisture — wet topsoil is heavier
Bulk bag volume
≈ 0.75m³
Standard bulk bag, roughly 900kg–1 tonne
Quick conversion
1 tonne ≈ 0.77m³
Handy for converting between weight and volume
When ordering topsoil, you'll typically see it sold by the tonne (loose loads) or by the bulk bag. Knowing the weight-to-volume ratio helps you compare prices between suppliers. For example, if you need 6m³ of topsoil, that's approximately 7.8 tonnes, or about 8 bulk bags.
Delivery tip: Check that your access can handle the delivery vehicle. Loose loads arrive on tipper lorries that need a firm, level surface to tip onto. Bulk bags are craned off and need roughly 1.5m × 1.5m of space each. If access is tight, bulk bags are usually the safer option.
Related guides
How Much Topsoil Do I Need?
Detailed guide to calculating topsoil quantities for any project.
Topsoil vs Compost: What's the Difference?
When to use topsoil, when to use compost, and when to mix them.
How Deep Should Topsoil Be?
Recommended depths for lawns, beds, raised beds, and veg patches.
BS3882 Topsoil Explained
What the British Standard means and why it matters.
Topsoil for a New Lawn
How to prepare topsoil for turf or seed.
Topsoil Delivery: What to Expect
Delivery methods, access requirements, and preparation tips.