Skip to content

Combined Gas Law Calculator

The Combined Gas Law Calculator helps determine the missing parameter among pressure, volume, and temperature by applying the combined gas law, which merges Boyle’s, Charles’s, and Gay-Lussac’s laws. It’s especially useful in thermodynamics and chemistry to analyze gas behavior when multiple variables change. Simply input five known values to solve for the sixth.

Combined Gas Law Calculator

Input Fields
K
K
If enabled, the result will update automatically when you change any value.

Combined Gas Law Formula

Formula
$$\frac{P_i \cdot V_i}{T_i} = \frac{P_f \cdot V_f}{T_f}$$

Where:

  • $$P_i$$, $$V_i$$, $$T_i$$ are the initial pressure, volume, and temperature
  • $$P_f$$, $$V_f$$, $$T_f$$ are the final pressure, volume, and temperature
  • Temperatures must be in Kelvin (K)
  • Pressures and volumes should use consistent units


The combined gas law is widely used in physics and chemistry when a gas undergoes changes involving pressure, volume, and temperature. It allows you to find one unknown variable when the other five are known. For example, you can calculate the final temperature after a gas is compressed or expanded, or determine the initial pressure before heating. It’s especially useful for laboratory experiments and industrial gas processes. Always ensure temperatures are converted to Kelvin and units are consistent to maintain accuracy.

Previous
Charles' Law

Leave a Reply

Your email address will not be published. Required fields are marked *