Bags of concrete per cubic metre
| Bag | Per m³ | Per yd³ | Source |
|---|---|---|---|
| Cement Australia Concrete Mix, PROSTRENGTH Extra Strength or PROSTRENGTH Rapid Set (20kg) | 110 | 84 | Cement Australia |
| Rapid Set Concrete (20kg) | 110 | 84 | Our estimate: no figure published, so the Concrete Mix figure is applied |
| Any 20kg bag of concrete mix | 110 | 84 | Our estimate from bag weight |
| Any 25kg bag of concrete mix | 88 | 67 | Our estimate from bag weight |
| Any 40lb bag of concrete mix | 121 | 93 | Our estimate from bag weight |
| Any 50lb bag of concrete mix | 97 | 74 | Our estimate from bag weight |
| Any 60lb bag of concrete mix | 81 | 62 | Our estimate from bag weight |
| Any 80lb bag of concrete mix | 61 | 46 | Our estimate from bag weight |
How much one bag of concrete makes
| Bag | Litres | Cubic feet | Source |
|---|---|---|---|
| Cement Australia 20kg | 9.1 | 0.32 | Cement Australia (110 per m³) |
| 20kg | 9.1 | 0.32 | Our estimate from bag weight |
| 25kg | 11.4 | 0.4 | Our estimate from bag weight |
| 40lb | 8.3 | 0.29 | Our estimate from bag weight |
| 50lb | 10.3 | 0.36 | Our estimate from bag weight |
| 60lb | 12.4 | 0.44 | Our estimate from bag weight |
| 80lb | 16.5 | 0.58 | Our estimate from bag weight |
Concrete mix ratios
Mixing from cement, sand and aggregate, Cement Australia uses 1 : 2 : 3 for paths and driveways and a leaner 1 : 3 : 3 for footings.
| Use | Cement : sand : aggregate | Source |
|---|---|---|
| Concrete, high strength or better water tightness | 1 : 1.5 : 3 | Cement Australia batching table, about 17 x 20kg bags of cement per m³ |
| Concrete for paths and driveways | 1 : 2 : 3 | Cement Australia batching table, about 16 x 20kg bags of cement per m³ |
| Concrete for foundations and footings | 1 : 3 : 3 | Cement Australia batching table, about 13 x 20kg bags of cement per m³ |
| Render (no aggregate) | 1 : 3 : 0 | Cement Australia batching table, about 20 x 20kg bags of cement per m³ |
Mortar mix ratios and cement bags per cubic metre
For mortar batched on site, Cement Australia gives 1 : 4 for general work and the more workable 1 : 6 : 1 with hydrated lime that AS 3700 calls M3. The bag counts are GP cement per cubic metre of mortar.
| Mortar | Cement : sand : hydrated lime | 20kg bags of cement per m³ | Source |
|---|---|---|---|
| General purpose mortar | 1 : 4 : 0 | 15 | Cement Australia batching table |
| More workable mortar (AS 3700 M3) | 1 : 6 : 1 | 8 | Cement Australia batching table and Hydrated Lime data sheet |
How much does concrete weigh?
| Amount | Weight of dry mix | Source |
|---|---|---|
| 1 m³ of concrete | 2,200kg (4850lb) | Our arithmetic: 110 x 20kg |
| 1 yd³ of concrete | 3710lb (1,682kg) | Our arithmetic |
| One 20kg bag | 20kg (44lb) | Bag weight |
| One 80lb bag | 80lb (36kg) | Bag weight |
Concrete unit conversions
| From | To | Multiply by |
|---|---|---|
| Cubic metres (m³) | Cubic yards (yd³) | 1.308 |
| Cubic yards (yd³) | Cubic metres (m³) | 0.765 |
| Cubic metres (m³) | Cubic feet (ft³) | 35.31 |
| Millimetres (mm) | Inches (in) | 0.0394 |
| Metres (m) | Feet (ft) | 3.281 |
| Kilograms (kg) | Pounds (lb) | 2.205 |
| Litres (L) | US quarts | 1.057 |
Questions
1 part cement, 2 parts sand and 3 parts aggregate by volume, about 16 x 20kg bags of cement per cubic metre (Cement Australia).
About 110 bags of Cement Australia concrete mix.
About 9.1 litres of placed concrete for a Cement Australia bag, or 9.1 litres by our estimate from bag weight.
The dry mix for 1 m³ weighs about 2,200kg (110 x 20kg), before the water goes in.
Yes. Use the citation line at the bottom of the page so readers can find the source and the date it was checked.
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Disclaimer
This calculator gives estimates from the sizes you enter, using manufacturers' published figures and standard geometry. It is not engineering or design advice. Footing, slab and beam sizes must come from your plans or engineer. Allow for site conditions, spillage and uneven ground. Check quantities with your supplier before ordering. Allmat accepts no responsibility for decisions made using these estimates.
Sources
- Cement Australia: frequently asked questions
- Cement Australia: volume batching mix table
- Cement Australia: Rapid Set Concrete
- Allmat arithmetic (this calculator)
Last checked 5 October 2026.
Cite this page
Allmat, "Concrete mix ratio and bags per m³", https://allmat.com.au/concrete-calculator/reference, checked 5 October 2026.