About

Liquefied Petroleum Gas (LPG/Propane) expands and contracts significantly with temperature changes. A cylinder filled with 20kg of propane will contain a different volume of liquid liters at -10°C compared to 30°C. This physical property is critical for safety; tanks must never be filled to 100% liquid capacity to allow for thermal expansion.

This tool uses the density curve of liquid propane to provide accurate conversions. While the standard industry rough estimate is often cited as 1 kg ≈ 1.96 Liters (at 15°C), this calculator adjusts that factor dynamically based on your ambient temperature input, ensuring precision for billing, tank filling, and inventory management.

Formulas

The volume is derived by dividing mass by the density at a specific temperature:

V = mρ(T)

Where:

V = Volume (L)
m = Mass (kg)
ρ(T) = Density at Temperature (kg/L)

Reference Data

Temp (°C)	Density (kg/L)	Volume of 1 kg (L)	10kg Cylinder (L)
-20°C	0.561	1.78	17.8
0°C	0.536	1.87	18.7
15°C (Std)	0.510	1.96	19.6
25°C	0.493	2.03	20.3
40°C	0.467	2.14	21.4

Frequently Asked Questions

As propane warms up, the liquid expands and becomes less dense. The mass (kg) remains the same, but it occupies more space (liters). This is why tanks have an "80% fill" safety valve.

This calculator uses the density curve for 100% Propane. Butane is denser (approx 0.58 kg/L at 15°C). LPG mixtures (Autogas) will fall somewhere in between depending on the Propane/Butane ratio.

The tool uses linear interpolation based on standard thermodynamic property tables for saturated liquid propane. It is accurate enough for commercial and industrial estimations.