API Gravity Calculator
Free calculate api gravity from specific gravity to measure petroleum liquid density relative to water.
Input Parameters
Density relative to water at 60°F (15.6°C)
Water density: 1000 kg/m³ at 4°C
Results
Enter specific gravity or density to calculate API gravity
API Gravity Formula
Formula
API = (141.5 / SG) - 131.5
Where:
- • API = API gravity (°API)
- • SG = specific gravity (at 60°F)
- • Water has SG = 1.0, API = 10°
API Gravity Ranges
- • Light crude: >31.1° API
- • Medium crude: 22.3-31.1° API
- • Heavy crude: 10-22.3° API
- • Extra heavy: <10° API
- • Water: 10° API