The density, or more precisely, the volumetric mass density of tantalum is 16650 kg/m³. This means that the mass of 1 m³ tantalum is 16650 kg.
The weight (on earth) of 1 m³ tantalum is 163336,5 N or 163,3365 kN.
Conversion Chart Metric System:
| Kilogram per cubic meter | 16650 | kg/m³ |
| Tonne per cubic meter | 16,65 | t/m³ |
| Gram per cubic meter | 16650000 | g/m³ |
| Milligram per cubic meter | 16650000000 | mg/m³ |
| Kilogram per cubic centimeter | 0,01665 | kg/cm³ |
| Gram per cubic centimeter | 16,65 | g/cm³ |
| Milligram per cubic centimeter | 16650 | mg/cm³ |
| Kilogram per litre | 16,65 | kg/L |
| Gram per litre | 16650 | g/L |
| Milligram per litre | 16650000 | mg/L |
| Kilogram per millilitre | 0,01665 | kg/mL |
| Gram per millilitre | 16,65 | g/mL |
| Milligram per millilitre | 16650 | mg/mL |
Conversion Chart British and U.S.:
| Pound per cubic yard | 28071,9 | lb/yd³ |
| Pound per cubic foot | 1039,4595 | lb/ft³ |
| Pound per cubic inch | 0,6015645 | lb/in³ |
| Pound per U.S. gallon | 138,94425 | lb/gal |
| Pound per British gallon | 166,833 | |
| Pound per U.S. bushel | 1293,5385 | |
| Ounce per cubic yard | 449050,5 | oz/yd³ |
| Ounce per cubic foot | 16630,02 | oz/ft³ |
| Ounce per cubic inch | 9,6237 | oz/in³ |
| Ounce per U.S. gallon | 2222,775 | oz/gal |
| Ounce per British gallon | 2670,66 | |
| Ounce per U.S. bushel | 20695,95 |
British Gravitational and English Engineering Units:
| Slug per cubic yard | 872,2935 | slug/yd³ |
| Slug per cubic foot | 32,301 | slug/ft³ |
| Slug per cubic inch | 0,01869795 | slug/in³ |