How to Use This Calculator

Enter the values of Enthalpy (ΔH), Entropy (ΔS), and Temperature (T) to calculate the Gibbs Free Energy (ΔG). The calculator auto-updates as you type.

What is Gibbs Free Energy?

Gibbs Free Energy determines whether a chemical reaction can occur spontaneously. A negative ΔG indicates a spontaneous reaction, while a positive value means non-spontaneous.

Formula

ΔG = ΔH - T × ΔS / 1000

Note: ΔS is divided by 1000 to convert from J to kJ for unit consistency.

Example

If ΔH = -100 kJ/mol, ΔS = 200 J/mol·K, and T = 298 K:

ΔG = -100 - (298 × 200 / 1000) = -100 - 59.6 = -159.6 kJ/mol