pyResToolbox MCP Server

Convert oil specific gravity to API gravity.

UNIT CONVERSION TOOL - Converts oil specific gravity (dimensionless, water=1.0) to API gravity (degrees). API gravity is an inverse measure of density - higher API means lighter oil. Essential for standardizing oil property reporting.

Parameters:

• sg (float or list, required): Oil specific gravity (water=1.0). Valid range: 0.1-1.5. Typical: 0.8-1.0. Example: 0.85 or [0.80, 0.85, 0.90]. Can be scalar or array.

Conversion Formula: API = (141.5 / SG) - 131.5

API Gravity Ranges:

• Heavy oil: API < 22° (SG > 0.922)

• Medium oil: API 22-35° (SG 0.922-0.850)

• Light oil: API > 35° (SG < 0.850)

• Water: API = 10° (SG = 1.0)

Returns: Dictionary with:

• value (float or list): API gravity in degrees (matches input sg shape)

• method (str): "Standard conversion"

• units (str): "degrees API"

• inputs (dict): Echo of input parameters

Common Mistakes:

• Using gas specific gravity instead of oil specific gravity

• Confusing API gravity with specific gravity (inverse relationship)

• Using density (lb/cuft) instead of specific gravity

• Not understanding that higher API = lighter oil

Example Usage:

Result: API = (141.5 / 0.85) - 131.5 ≈ 35.0° (medium gravity oil)

Note: API gravity is the industry standard for oil classification. Use this conversion when you have specific gravity but need API gravity for correlations or reporting.