The density, or more precisely, the volumetric mass density of rhenium is 21020 kg/m³. This means that the mass of 1 m³ rhenium is 21020 kg.
The weight (on earth) of 1 m³ rhenium is 206206,2 N or 206,2062 kN.
Conversion Chart Metric System:
| Kilogram per cubic meter | 21020 | kg/m³ |
| Tonne per cubic meter | 21,02 | t/m³ |
| Gram per cubic meter | 21020000 | g/m³ |
| Milligram per cubic meter | 21020000000 | mg/m³ |
| Kilogram per cubic centimeter | 0,02102 | kg/cm³ |
| Gram per cubic centimeter | 21,02 | g/cm³ |
| Milligram per cubic centimeter | 21020 | mg/cm³ |
| Kilogram per litre | 21,02 | kg/L |
| Gram per litre | 21020 | g/L |
| Milligram per litre | 21020000 | mg/L |
| Kilogram per millilitre | 0,02102 | kg/mL |
| Gram per millilitre | 21,02 | g/mL |
| Milligram per millilitre | 21020 | mg/mL |
Conversion Chart British and U.S.:
| Pound per cubic yard | 35439,72 | lb/yd³ |
| Pound per cubic foot | 1312,2786 | lb/ft³ |
| Pound per cubic inch | 0,7594526 | lb/in³ |
| Pound per U.S. gallon | 175,4119 | lb/gal |
| Pound per British gallon | 210,6204 | |
| Pound per U.S. bushel | 1633,0438 | |
| Ounce per cubic yard | 566909,4 | oz/yd³ |
| Ounce per cubic foot | 20994,776 | oz/ft³ |
| Ounce per cubic inch | 12,14956 | oz/in³ |
| Ounce per U.S. gallon | 2806,17 | oz/gal |
| Ounce per British gallon | 3371,608 | |
| Ounce per U.S. bushel | 26127,86 |
British Gravitational and English Engineering Units:
| Slug per cubic yard | 1101,2378 | slug/yd³ |
| Slug per cubic foot | 40,7788 | slug/ft³ |
| Slug per cubic inch | 0,02360546 | slug/in³ |