Unit Conversions · Engineering & science · Fluids, gases & aerodynamics

Ideal Gas Law Calculator

Solve pressure, volume, amount, or absolute temperature and report molar density and number of molecules with every absolute unit made explicit.

Unit Conversions · Engineering & science · Fluids, gases & aerodynamics

Ideal Gas Law Calculator

Private in-browser calculation · explicit units, solve direction, assumptions, reconciliation, and companion outputs

Leave the field selected as the unknown blank; enter the other required values.

Calculation result

Enter valid values to see the result.

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Quick guide

How to use this calculator

  1. Choose the physical relationship and solve direction that match the known measurements rather than forcing unlike quantities into one formula.
  2. Enter every unit, sign, reference direction, geometry, material property, fluid property, temperature basis, coefficient, and idealization explicitly. The calculator normalizes compatible quantities internally and exposes intermediate values.
  3. Use reconciliation and companion outputs to catch entry mistakes, then retain the stated model boundary. A theoretical result is not a design approval, material certificate, equipment rating, or safety determination.

Calculation method

How the ideal gas law calculator works

Provide an explicit molar ideal-gas workflow without hiding absolute units or supplying an assumed gas composition.

PV=nRT using R=8.31446261815324 J/(mol·K). Pressure and temperature are absolute after conversion.

Worked example

Ideal Gas Law example

One mole at 25 °C and 101.325 kPa occupies about 24.466 L under the ideal-gas model.

PV=nRT using R=8.31446261815324 J/(mol·K). Pressure and temperature are absolute after conversion.

Supported inputs

Precision and limits

Engineering-model boundary

Real-gas behavior, compressibility factor, reactions, condensation, mixtures, humidity, and changing heat capacities are excluded. Never enter gauge pressure as absolute pressure.

Units and precision

Calculations normalize compatible inputs to SI, retain working precision, and round only for display. Very small and large nonzero values use scientific notation; displayed digits cannot create accuracy beyond the entered measurements and properties.

Decision boundary

This page solves the declared idealized relationship only. Verify applicable material data, operating conditions, geometry, loads, coefficients, standards, codes, manufacturer requirements, uncertainty, and professional approval before consequential use.

Category ownership

Generic mechanics, materials, fluid, aerodynamic, wave, and thermodynamic relationships live here. Trade-specific pipe, HVAC, motor, electrical, construction, automotive, radiation, statistical, chemical, and astronomical workflows remain with their established categories.

Privacy

Entered values and results stay in this browser and are not sent to analytics or third parties.

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