Charles's Law Calculator
Volume and temperature at constant pressure.
Enter your values
Enter the initial volume in L.
Enter the initial temperature in K.
Enter the final temperature in K.
Results update instantly as you type — no submit needed. Your values are remembered on this device, and the shareable link reopens the calculator with exactly these numbers.
- Final volume
- 3.1292 L
- Volume change
- 0.6292 L
- Temperature ratio
- 1.2517
- Initial temperature in °C
- 24.85
- Final temperature in °C
- 99.85
Quick answer
At constant pressure, gas volume is directly proportional to absolute temperature in kelvin.
V₁/T₁ = V₂/T₂
At a glance
| What it does | Volume and temperature at constant pressure. |
|---|---|
| Category | Science |
| Inputs needed | Initial volume, Initial temperature, Final temperature |
| Main output | Final volume |
| Formula | V₁/T₁ = V₂/T₂ |
| Cost | Free — no sign-up, no download |
How to use the Charles's Law Calculator
- 1Enter the initial volume.
- 2Enter both temperatures in kelvin.
- 3Convert °C to K by adding 273.15.
Inputs explained
- Initial volume(L)
- Enter the initial volume in L.
- Initial temperature(K)
- Enter the initial temperature in K.
- Final temperature(K)
- Enter the final temperature in K.
Worked example
Using the values the calculator loads with:
Inputs
- Initial volume2.5 L
- Initial temperature298 K
- Final temperature373 K
Results
- Final volume3.1292 L
- Volume change0.6292 L
- Temperature ratio1.2517
- Initial temperature in °C24.85
- Final temperature in °C99.85
Frequently asked questions
Why kelvin?
The law is proportional to absolute temperature; celsius would give nonsense at low values.
What happens at 0 K?
Volume theoretically goes to zero — real gases liquefy long before then.
What do I need to enter into the Charles's Law Calculator?
Just 3 values: initial volume, initial temperature, final temperature. Every field starts with a realistic example, so you can change one number at a time and watch the result update instantly.
How does the Charles's Law Calculator work out the answer?
At constant pressure, gas volume is directly proportional to absolute temperature in kelvin. It applies the formula V₁/T₁ = V₂/T₂ and shows the working so you can check each step by hand.
Is the Charles's Law Calculator free, and do I need an account?
It is completely free with no sign-up, no download and no usage limit. Everything is calculated in your browser, so the numbers you type never leave your device.
Results are estimates for general information. For medical, legal, structural or financial decisions, confirm with a qualified professional.