Understand the engineering model
What is Ideal Gas Law?
Fluid and aerodynamic models connect density, pressure, flow, velocity, geometry, viscosity, gas state, and coefficient-based forces while preserving the stated control volume and reference conditions.
Provide an explicit molar ideal-gas workflow without hiding absolute units or supplying an assumed gas composition.
The relationship
Write the model before substituting values
PV=nRT using R=8.31446261815324 J/(mol·K). Pressure and temperature are absolute after conversion.
See the calculation
From measurement to engineering result
1Fluid state and geometry2Continuity or energy model3Flow, pressure, or force
Worked context
Read the output with its units
One mole at 25 °C and 101.325 kPa occupies about 24.466 L under the ideal-gas model.
Interpret with care
Important model boundary
Real-gas behavior, compressibility factor, reactions, condensation, mixtures, humidity, and changing heat capacities are excluded. Never enter gauge pressure as absolute pressure.
A calculated value does not certify a component, material, installation, operating envelope, code requirement, or safety decision. Check measurements, signs, standards, uncertainty, and professional approval where consequences matter.
Browse Engineering & science for connected physical relationships.
Quick guide
How to use this calculator
- Choose the physical relationship and solve direction that match the known measurements rather than forcing unlike quantities into one formula.
- 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.
- 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.
Continue calculating
Related calculators
