Gas Laws Calculator

Calculate gas properties using various gas laws.

Updated: November 2025 • Free Tool

Select Law

Note: Temperature must be in Kelvin for calculations (or handled automatically). Leave one field blank to calculate it.

Result

Result
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What are Gas Laws?

Gas Laws are mathematical relationships that describe how pressure, volume, temperature, and amount of gas are related for ideal gases.

These laws help predict gas behavior in chemical reactions, industrial processes, and everyday situations like weather patterns.

To convert moles to mass or vice-versa, use our Mole & Molar Mass Calculator.

Gas Law Formulas

  • Ideal Gas Law: PV = nRT
  • Boyle's Law: P₁V₁ = P₂V₂
  • Charles's Law: V₁/T₁ = V₂/T₂
  • Gay-Lussac's Law: P₁/T₁ = P₂/T₂
  • Combined: P₁V₁/T₁ = P₂V₂/T₂

Key Concepts

  • Ideal Gas Assumption: No intermolecular forces and particles have no volume.
  • Temperature in Kelvin: Always use absolute temperature (Kelvin) in calculations.
  • STP Conditions: Standard temperature (273.15 K) and pressure (1 atm).

How to Use This Calculator

1

Select Gas Law

Choose from Ideal, Boyle's, Charles's, etc.

2

Enter Known Values

Input all known variables.

3

Calculate Unknown

Get the missing variable instantly.

Benefits of Using This Calculator

  • Multiple Laws: Access all major gas laws in one calculator.
  • Flexible Solving: Calculate any unknown from known values.
  • Educational Tool: Perfect for chemistry and physics students.

Standard Constants

  • R (Ideal Gas Constant): 0.0821 L·atm/(mol·K) or 8.314 J/(mol·K).
  • STP (Standard Temperature and Pressure): 0°C (273.15 K) and 1 atm.
Gas Laws Calculator
Gas Laws Calculator interface for solving physics and chemistry gas problems.

Frequently Asked Questions (FAQ)

Q: What is the Ideal Gas Law?

A: The Ideal Gas Law is the equation of state of a hypothetical ideal gas. It is PV = nRT, where P is pressure, V is volume, n is amount of substance (moles), R is the ideal gas constant, and T is temperature.

Q: What is Boyle's Law?

A: Boyle's Law states that the pressure of a given mass of an ideal gas is inversely proportional to its volume at a constant temperature (P₁V₁ = P₂V₂).

Q: What is Charles's Law?

A: Charles's Law states that the volume of an ideal gas is directly proportional to its absolute temperature at constant pressure (V₁/T₁ = V₂/T₂).