Density Converter
Print pageAll Equivalents Reference Table
| Unit | Equivalent Value |
|---|
Mass density (symbolized by ρ) quantifies the amount of mass contained within a given unit volume of a substance (ρ = m ÷ V). Across chemical processing, civil foundation design, metallurgy, fluid mechanics, oceanography, astrophysics, and material quality assurance, volumetric density is expressed in four global unit families: International System of Units (SI metric base: Kilograms per Cubic Meter / kg/m3), laboratory metric standards (Grams per Cubic Centimeter / g/cm3, Kilograms per Liter / kg/L, Grams per Liter / g/L), Imperial structural engineering metrics (Pounds per Cubic Foot / lb/ft3, Pounds per Cubic Inch / lb/in3, Slugs per Cubic Foot / slug/ft3), and liquid delivery ratings (Pounds per US Gallon / lb/gal US, Pounds per UK Gallon / lb/gal UK).
Our free online Density Converter provides instant, high-precision conversions across all SI metric, CGS laboratory, Imperial engineering, and astrophysical density units:
- Grams per Cubic Centimeter to kg/m3 (g/cm3 to kg/m3): Multiply g/cm3 by
1,000(1 g/cm3 = 1,000 kg/m3 = 1.0 kg/L = 62.42796 lb/ft3 = 8.3454 lb/gal US). - Pounds per Cubic Foot to kg/m3 (lb/ft3 to kg/m3): Multiply lb/ft3 by
16.018463(1 lb/ft3 = 16.0185 kg/m3 = 0.0160185 g/cm3). - Pounds per Cubic Inch to kg/m3 (lb/in3 to kg/m3): Multiply lb/in3 by
27,679.9047(1 lb/in3 = 27.6799 g/cm3 = 1,728 lb/ft3). - Slug per Cubic Foot to kg/m3: Multiply slug/ft3 by
515.378818(1 slug/ft3 = 515.379 kg/m3 = 32.174 lb/ft3). - Pounds per US Gallon to kg/m3: Multiply lb/gal US by
119.826427(Water = 8.345 lb/gal US = 1,000 kg/m3). - Mean Earth Planetary Density (ρearth):
5,518 kg/m3 = 5.518 g/cm3 = 344.48 lb/ft3.
Master Mass Density Unit Conversion Table
The table below displays exact mathematical relationships, SI kg/m3 multipliers, and imperial equivalents relative to 1 Gram per Cubic Centimeter (1 g/cm3 = 1.0 kg/L):
| Density Unit Name | Symbol | Exact Value in kg/m3 | g/cm3 & lb/ft3 Equivalent | Domain & Technical Application Standard |
|---|---|---|---|---|
| 1 Gram per Cubic Centimeter | g/cm3, g/mL |
1,000.0 kg/m3 |
1.0 g/cm3 (62.42796 lb/ft3 / 8.3454 lb/gal US) |
CGS Laboratory & Water Reference Standard |
| 1 Kilogram per Cubic Meter | kg/m3 |
1.0 kg/m3 (Base SI Unit) |
0.001 g/cm3 (0.062428 lb/ft3 / 1.0 g/L) |
SI Fundamental Volumetric Mass Density Standard |
| 1 Kilogram per Liter | kg/L |
1,000.0 kg/m3 |
1.0 g/cm3 (62.42796 lb/ft3) |
Chemical Process Engineering & Liquid Handling |
| 1 Pound per Cubic Foot | lb/ft3, pcf |
16.018463 kg/m3 |
0.0160185 g/cm3 (1.0 lb/ft3 / 0.13368 lb/gal) |
US Civil Engineering Structural Load Standard |
| 1 Pound per Cubic Inch | lb/in3 |
27,679.905 kg/m3 |
27.6799 g/cm3 (1,728.0 lb/ft3) |
Aerospace & Mechanical CAD Material Weight |
| 1 Slug per Cubic Foot | slug/ft3 |
515.37882 kg/m3 |
0.515379 g/cm3 (32.17405 lb/ft3) | Imperial Aerodynamic & Fluid Dynamic Mass Density |
| 1 Pound per US Gallon | lb/gal (US) |
119.82643 kg/m3 |
0.119826 g/cm3 (7.48052 lb/ft3) | US Petroleum & Chemical Fuel Batching |
| 1 Pound per UK Imperial Gallon | lb/gal (UK) |
99.77637 kg/m3 |
0.099776 g/cm3 (6.22884 lb/ft3) | UK & Commonwealth Chemical Fuel Metric |
| 1 Gram per Liter | g/L |
1.0 kg/m3 |
0.001 g/cm3 (0.062428 lb/ft3) | Gas Density & Water Solution Salinity |
| 1 Mean Earth Density | Earth ρ |
5,518.0 kg/m3 |
5.518 g/cm3 (344.48 lb/ft3) |
Planetary Geophysics & Astronomical Reference |
Step-by-Step Material Density Calculation Example
To convert structural steel with a density of 7.85 Grams per Cubic Centimeter (7.85 g/cm3) into SI kg/m3, Imperial lb/ft3, and lb/in3:
Step 1 (SI kg/m3): 7.85 × 1,000 = 7,850.0 kg/m3
Step 2 (Imperial lb/ft3): 7,850 ÷ 16.018463 = 490.060 lb/ft3 (490.06 lb/ft3)
Step 3 (Imperial lb/in3): 7.85 ÷ 27.679905 = 0.283598 lb/in3 (0.2836 lb/in3)
Thus, structural steel (7.85 g/cm3) equals 7,850 kg/m3 (or 490.06 lb/ft3 / 0.2836 lb/in3).
Real-World Material, Liquid & Astrophysical Density Benchmarks
Below is a comparative reference chart showing density values across air, water, structural metals, gold, Earth, the Sun, and neutron stars:
| Substance / Physical Environment | Density in Laboratory Metric (g/cm3) | Density in SI & Imperial (kg/m3 / lb/ft3) | Physical & Technical Context |
|---|---|---|---|
| Dry Air (at 15°C, 1 atm Sea Level) | 0.001225 g/cm3 (1.225 g/L) | 1.225 kg/m3 (0.07647 lb/ft3) | Standard International Atmosphere (ISA) sea-level air density |
| Pure Liquid Water (at 4°C Peak Density) | 1.000 g/cm3 (1.0 kg/L) | 1,000.0 kg/m3 (62.428 lb/ft3 / 8.345 lb/gal US) | Universal reference benchmark for specific gravity calculations |
| Aluminum Metal (Element 13) | 2.700 g/cm3 | 2,700.0 kg/m3 (168.56 lb/ft3 / 0.0975 lb/in3) | Lightweight structural aerospace metal alloy base |
| Pure Iron / Carbon Structural Steel | 7.874 g/cm3 | 7,874.0 kg/m3 (491.56 lb/ft3 / 0.2844 lb/in3) | Global construction beam and civil engineering metal |
| Pure Gold (Element 79) | 19.300 g/cm3 | 19,300.0 kg/m3 (1,204.86 lb/ft3 / 0.6972 lb/in3) | Precious heavy metal with extreme volumetric density |
| Osmium Metal (Densest Natural Element 76) | 22.590 g/cm3 | 22,590.0 kg/m3 (1,410.24 lb/ft3 / 0.8161 lb/in3) | Highest naturally occurring elemental mass density on Earth |
| Solar Core Density (Sun Interior) | 150.0 g/cm3 | 150,000.0 kg/m3 (9,364.0 lb/ft3) | Extreme gravitational compression at core of the Sun |
| Neutron Star Core Matter | 4.0 × 1014 g/cm3 | 4.0 × 1017 kg/m3 (2.5 × 1016 lb/ft3) | Quantum degenerate matter (1 teaspoon equals 4 billion tons) |
History & Physics: c. 250 BC Archimedes Crown “Eureka” vs. 1798 Cavendish Earth Density Experiment
c. 250 BC Archimedes & the Gold Crown “Eureka” Discovery
Around 250 BC, Greek mathematician Archimedes of Syracuse discovered fluid displacement while taking a bath to determine if King Hiero II’s crown was pure gold or alloyed with cheaper silver. Archimedes realized that submerging the crown displaced a volume of water exactly equal to its own volume. Dividing mass by displaced volume (ρ = m ÷ V) proved the crown was less dense than pure gold (19.3 g/cm3 vs silver’s 10.5 g/cm3). This laid the foundation for hydrostatics and mass density measurement.
1798 Henry Cavendish & Measuring Earth’s Density
In 1798, British scientist Henry Cavendish completed his famous torsion balance experiment to measure the gravitational constant G and calculate the mean density of planet Earth. Cavendish determined Earth’s average density to be 5,448 kg/m3 (5.448 times denser than water), coming within 1% of modern satellite measurements (5,518 kg/m3). This proved that Earth’s core consists of dense iron-nickel metal rather than hollow space or solid rock.
Popular direct tools:
Frequently Asked Questions (FAQ)
How do you convert g/cm3 to kg/m3?
To convert Grams per Cubic Centimeter (g/cm3) to Kilograms per Cubic Meter (kg/m3), multiply by 1,000. For example, 2.7 g/cm3 × 1,000 = 2,700 kg/m3.
How do you convert lb/ft3 to kg/m3?
To convert Pounds per Cubic Foot (lb/ft3) to kg/m3, multiply lb/ft3 by 16.018463 (e.g., 62.43 lb/ft3 × 16.0185 = 1,000 kg/m3).
What is the density of pure water in kg/m3 and lb/gal?
At 4°C, pure water has a density of exactly 1,000 kg/m3 (1.0 g/cm3 / 1.0 kg/L), which equals 62.428 lb/ft3 or 8.3454 lb/gal (US).
What is the densest naturally occurring element on Earth?
The densest natural element is Osmium (Os), with a mass density of 22.59 g/cm3 (22,590 kg/m3 / 1,410.24 lb/ft3), slightly exceeding Iridium (22.56 g/cm3) and Platinum (21.45 g/cm3).