Calculate volume changes of a gas with temperature using Charles's Law (V₁/T₁ = V₂/T₂). Supports °C, °F, K with work done and gas law reference.
The **Charles's Law Calculator** applies Jacques Charles's 1787 discovery: the volume of a gas is directly proportional to its absolute temperature when pressure is held constant. Enter an initial volume and temperature, specify a new temperature, and instantly see the resulting volume, percentage change, work done, and the proportionality constant.
Charles's Law is one of the fundamental gas laws that combine into the ideal gas equation PV = nRT. It explains why hot air balloons rise, why tyre pressures increase on a hot day, and why a balloon shrinks in a freezer. The law requires temperatures in the absolute (Kelvin) scale; this calculator handles conversion from Celsius, Fahrenheit, or Kelvin automatically.
Explore presets for balloons, tyres, lab syringes, hot air balloons, and cryogenic cooling, and reference the comparison table of all major gas laws.
Use the preset examples to load common values instantly, or type in custom inputs to see results in real time. The output updates as you type, making it practical to compare different scenarios without resetting the page.
Charles's Law is essential for understanding gas behaviour in chemistry, physics, meteorology, and engineering. This calculator provides instant volume predictions, work done, and a comprehensive gas-law reference table.
This tool is designed for quick, accurate results without manual computation. Whether you are a student working through coursework, a professional verifying a result, or an educator preparing examples, accurate answers are always just a few keystrokes away.
Charles's Law: V₁/T₁ = V₂/T₂ (constant pressure) Final Volume: V₂ = V₁ × (T₂/T₁) Work Done (isobaric): W = P × ΔV Temperatures must be in Kelvin: K = °C + 273.15
Result: V₂ = 2.671 L (+6.83%)
Heating a 2.5 L gas sample from 20°C (293.15 K) to 40°C (313.15 K) increases its volume to 2.671 L — a 6.83% expansion.
Use consistent units throughout your calculation and verify all assumptions before treating the output as final. For professional or academic work, document your input values and any conversion standards used so results can be reproduced. Apply this calculator as part of a broader workflow, especially when the result feeds into a larger model or report.
Most mistakes come from mixed units, rounding too early, or misread labels. Recheck each final value before use. Pay close attention to sign conventions — positive and negative inputs often produce very different results. When working with multiple related calculations, keep intermediate values available so you can trace discrepancies back to their source.
Enter the most precise values available. Use the worked example or presets to confirm the calculator behaves as expected before entering your real data. If a result seems unexpected, compare it against a manual estimate or a known reference case to catch input errors early.
At constant pressure, the volume of an ideal gas is directly proportional to its absolute (Kelvin) temperature: V ∝ T. Use this as a practical reminder before finalizing the result.
Charles's Law describes a proportional relationship V/T = constant. This only works with an absolute scale where zero means zero molecular motion. Using °C or °F would give incorrect results.
It works well at moderate temperatures and pressures. Real gases deviate at very high pressures or near their liquefaction temperature.
Theoretically, volume goes to zero. In practice, all gases liquefy and then solidify before reaching 0 K.
Boyle's Law (PV = const) keeps temperature constant and varies pressure/volume. Charles's Law keeps pressure constant and varies temperature/volume.
A process at constant pressure. Charles's Law applies only to isobaric processes (or at least nearly constant pressure, like an open container).