Cubic Metres, Tonnes and Truckloads: How to Work Out How Much Fill You’re Moving
One of the most common questions on any earthworks or landscaping job is deceptively simple: how much fill is actually being moved? Get the number wrong and you either pay for trucks you don’t need or come up short halfway through the job. This guide breaks down cubic metres, tonnes and truckloads in plain English, so you can size a job confidently before a single load leaves the site.
Start with volume: cubic metres
Fill is almost always measured by volume first, in cubic metres (m³). Working out volume is straightforward for a regular shape:
Length (m) × Width (m) × Depth (m) = Volume (m³)
For example, a pad that’s 10 m long, 8 m wide and 0.3 m deep needs 10 × 8 × 0.3 = 24 m³ of fill. For irregular areas, break the site into rectangles, work out each one, and add them together. Always measure depth as the finished level minus the current ground level — not just how deep you think the hole looks.
From cubic metres to tonnes
Trucks and tips often charge by weight (tonnes), not volume, so you’ll need to convert. The catch is that different materials weigh different amounts per cubic metre:
- Clean fill / general soil: roughly 1.5–1.8 tonnes per m³
- Sand: roughly 1.5 tonnes per m³
- Gravel and road base: roughly 1.8–2.2 tonnes per m³
- Wet clay: can exceed 2.0 tonnes per m³
As a rule of thumb, multiply your cubic metres by about 1.6 for ordinary fill to estimate tonnes. So our 24 m³ pad above is roughly 24 × 1.6 = 38 tonnes. Moisture matters a lot here — wet material is significantly heavier, which is why the same hole can cost more to fill after rain.
How many truckloads is that?
Truck capacity varies widely, so always confirm with your carrier. As a general guide:
- Small tipper (2–3 tonne ute/truck): around 1.5–2 m³
- Standard tipper truck: around 6–8 m³ (roughly 10–13 tonnes)
- Truck and dog (trailer combo): around 16–22 m³ (roughly 25–35 tonnes)
For our 24 m³ example, that’s roughly three to four standard tipper loads, or a single truck-and-dog load. Fewer, larger loads usually cost less per cubic metre — but only if the site can physically take a bigger truck.
Always add a margin
Fill compacts once it’s placed and rolled, so loose material from the truck will settle to a smaller finished volume. It’s normal to order around 10–20% more than your raw calculation to allow for compaction, spillage and uneven ground. It’s far cheaper to have a little left over than to halt a job waiting on one more load.
Why getting the number right matters
Accurate quantities affect everything downstream: how many trucks you book, what you pay in cartage, whether a tip site can take the whole job, and how long the work takes. When you post a job on ReadyFill, having a realistic volume in mind helps you connect with the right tip sites and suppliers straight away — no back-and-forth, no half-finished pads.
Need somewhere to send excess fill, or looking to bring clean fill onto your site? ReadyFill matches people who have material with those who need it, based on location and material type — so you spend less time chasing loads and more time getting the job done.