Convert cubic feet to metric tonnes using the density of the material you are measuring. This calculator is especially useful for concrete quantity planning because volume alone does not determine weight. Enter cubic feet, choose or enter a density, and calculate tonnes, kilograms and cubic metres without relying on a misleading one-size-fits-all conversion.
Cubic feet measure volume while tonnes measure mass. Select a mode, then supply the material density required to connect the two units.
Your Result Will Appear Here After You Press Calculate Conversion.
The PDF Includes The Site Name, Conversion Mode, Input, Density, Cubic Metres, Kilograms And Tonnes.
Cubic feet describe how much space a material occupies. Tonnes describe how much mass it has. Density is the link between those two measurements.
The tool separates volume, density and mass so you can see exactly how the conversion is produced.
Enter the material volume in cubic feet when starting from an imperial quantity.
Use the actual density in kilograms per cubic metre where possible.
See the intermediate metric volume used in the mass calculation.
View the calculated mass before it is divided by 1000 into tonnes.
See the final metric tonne estimate based on your selected density.
Zero appears only as a placeholder, so typing a number never creates a leading zero.
A cubic foot is a unit of volume. A metric tonne is a unit of mass equal to 1,000 kilograms. Because volume and mass describe different physical properties, there is no single universal number that converts every cubic foot into tonnes. The missing information is density: how much mass a particular material contains in a given volume.
The correct workflow is to convert cubic feet into cubic metres, multiply the cubic metres by the material density in kilograms per cubic metre, and then divide kilograms by 1,000 to obtain metric tonnes. The exact cubic-foot-to-cubic-metre factor is 0.028316846592.
Tonnes = ft³ × 0.028316846592 × Density (kg/m³) ÷ 1000Two materials can occupy exactly the same 10 cubic feet but have very different weights. A dense concrete mix will weigh far more than a lightweight fill or insulation material occupying the same space. Moisture, compaction, aggregate type, void content and product composition can also affect density. That is why the calculator asks for density rather than pretending that one fixed ft³-to-tonnes factor applies everywhere.
For concrete planning, a density around 2,400 kg/m³ is commonly used as a rough normal-weight concrete example, but actual concrete density varies with mix design and materials. If you have a project specification, supplier data sheet or measured unit weight, enter that value instead. At 2,400 kg/m³, one cubic foot corresponds to about 67.96 kg, or about 0.06796 metric tonne.
| Cubic Feet | Cubic Metres | Kilograms | Metric Tonnes |
|---|---|---|---|
| 1 ft³ | 0.028317 m³ | 67.96 kg | 0.06796 t |
| 5 ft³ | 0.141584 m³ | 339.80 kg | 0.33980 t |
| 10 ft³ | 0.283168 m³ | 679.60 kg | 0.67960 t |
| 25 ft³ | 0.707921 m³ | 1,699.01 kg | 1.69901 t |
| 50 ft³ | 1.415842 m³ | 3,398.02 kg | 3.39802 t |
| 100 ft³ | 2.831685 m³ | 6,796.04 kg | 6.79604 t |
The reverse calculation also needs density. Convert tonnes to kilograms by multiplying by 1,000, divide by density to obtain cubic metres, then divide by 0.028316846592 to obtain cubic feet.
ft³ = Tonnes × 1000 ÷ Density (kg/m³) ÷ 0.028316846592If kilograms are more useful than tonnes, stop the calculation before dividing by 1,000. Multiply cubic feet by 0.028316846592 to obtain cubic metres, then multiply by density. The calculator includes a dedicated ft³-to-kilograms mode for this purpose.
The best density is the one that describes the actual material in the actual condition you are estimating. For ready-mixed concrete, project or supplier information may give unit mass or density. For bagged products, product literature may provide density or yield. For soil, sand and aggregate, bulk density can change substantially with moisture and compaction. If the material is safety-critical, structural or commercially significant, do not substitute a generic online density for project data.
| Density Example | Density | Mass Of 10 ft³ | Tonnes |
|---|---|---|---|
| Water Reference | 1,000 kg/m³ | 283.17 kg | 0.28317 t |
| Lower Concrete Example | 2,300 kg/m³ | 651.29 kg | 0.65129 t |
| Normal Concrete Example | 2,400 kg/m³ | 679.60 kg | 0.67960 t |
| Dense Concrete Example | 2,500 kg/m³ | 707.92 kg | 0.70792 t |
This page uses the metric tonne, symbol t, which equals exactly 1,000 kilograms. A US short ton and an imperial long ton are different units. If a supplier quote or project document says “tons,” check which ton definition is intended before comparing values.
Assume a planning density of 2,400 kg/m³. First convert 20 ft³ to cubic metres: 20 × 0.028316846592 = 0.56633693184 m³. Multiply by 2,400 kg/m³ to obtain about 1,359.21 kg. Divide by 1,000 to obtain about 1.35921 tonnes.
Assume the same example density of 2,400 kg/m³. Two tonnes equals 2,000 kg. Divide by 2,400 to obtain 0.833333 m³. Divide by 0.028316846592 and the result is approximately 29.43 ft³.
A cubic feet to tonnes calculator can help with concrete planning, demolition estimates, material logistics, transport checks, aggregate quantities, bulk storage and cross-unit supplier comparisons. It is especially useful when one source gives volume while another gives mass. For concrete ordering, however, suppliers commonly sell ready-mixed concrete by volume, so you may also want the Cubic Feet to Cubic Metres, Cubic Yards to Cubic Metres, Concrete Volume Calculator and Concrete Delivery Calculator.
Continue with Cubic Feet to Cubic Metres, Cubic Feet to Cubic Yards, Cubic Metres to Cubic Feet, kg/m³ to lb/ft³ and Concrete Quantity Calculator when you need related volume or density conversions.
These examples use an illustrative concrete density of 2,400 kg/m³. Change the density when your material is different.
| Example | Volume | Density | Calculation | Tonnes |
|---|---|---|---|---|
| Small Quantity | 3 ft³ | 2,400 kg/m³ | 3 × 0.028316846592 × 2400 ÷ 1000 | 0.204 t |
| Medium Quantity | 12 ft³ | 2,400 kg/m³ | 12 × 0.028316846592 × 2400 ÷ 1000 | 0.815 t |
| Large Quantity | 30 ft³ | 2,400 kg/m³ | 30 × 0.028316846592 × 2400 ÷ 1000 | 2.039 t |
| One Cubic Yard Equivalent | 27 ft³ | 2,400 kg/m³ | 27 × 0.028316846592 × 2400 ÷ 1000 | 1.835 t |
Quick answers about density, concrete mass, cubic feet, kilograms and metric tonnes.
There is no universal answer because tonnes measure mass and cubic feet measure volume. You need the material density. At an example density of 2,400 kg/m³, 1 ft³ is about 0.06796 metric tonne.
Multiply cubic feet by 0.028316846592 to obtain cubic metres, multiply by density in kg/m³, then divide by 1,000.
Using an illustrative density of 2,400 kg/m³, 10 ft³ is about 0.6796 metric tonne. Actual concrete density can differ.
Use the density specified by your supplier, mix design, engineer or product data when available. The calculator offers 2,400 kg/m³ only as a common planning example, not a universal concrete value.
Yes, but the reverse calculation still requires density. Divide the mass in kilograms by density to obtain cubic metres, then convert cubic metres to cubic feet.
No. A metric tonne equals exactly 1,000 kilograms. A US short ton is a different mass unit.
Density is the physical link between volume and mass. Without it, a cubic-feet-to-tonnes conversion is incomplete.
The input starts visually at zero but contains no actual numeric zero. Typing 25 therefore produces 25 rather than 025.
The result remains hidden until you press Calculate Conversion so an empty or zero state is not mistaken for a completed estimate.
Use recognised unit definitions and project-specific material information whenever accuracy matters.
Reference material for SI measurement units and unit conversion practice.
View NIST SI InformationAustralian concrete industry information and technical resources.
Visit CCAA