Vapor Pressure of Water Calculator

Ever wondered how water turns into vapor? It all comes down to vapor pressure. At any given temperature, water has a natural push to change into gas. This push is its vapor pressure. Our Vapor Pressure of Water Calculator helps you find it fast. No tough math, no long tables. Just type the temperature, and you’ll see the result in seconds.

What is Vapor Pressure of Water?

Vapor pressure is the force made by water molecules escaping into the air. The warmer the water, the higher the vapor pressure. Think about a cup of tea. When it’s hot, steam rises quickly. That’s vapor pressure in action. At room temperature, water still has vapor pressure, but it’s much lower.

Why Use a Calculator?

You could use big charts or long formulas. But let’s be real who has time for that? Our water vapor pressure calculator does the job for you. It’s simple, quick, and accurate. Whether you’re a student, a researcher, or just curious, this tool saves you from headaches.

How to Calculate Vapor Pressure

Scientists use equations to find vapor pressure. Here are the most common ones:

Antoine Equation

P = 10^(A − B / (C + T))

Where:

• P is vapor pressure (mmHg)
• T is temperature in °C
• A, B, C are constants

Buck Formula

P = 0.61121 × exp((18.678 − T / 234.5) × (T / (257.14 + T)))

Here P is in kPa, and T is in °C.

These formulas may look scary, but don’t worry. Our calculator runs them for you in the background.

Vapor Pressure of Water at 25 °C

At 25 °C, the vapor pressure of water is:

23.8 mmHg

3.17 kPa

This is the standard value you’ll often see in textbooks.

How to Use the Calculator

1. Enter the temperature in Celsius, Fahrenheit, or Kelvin.
2. Choose the formula you want (Antoine, Buck, Magnus, Tetens, or Simple).
3. Hit “Calculate.”
4. Get instant results in kPa, mmHg, atm, psi, and more.

It’s as easy as brewing your morning coffee.

Final Verdict

The Vapor Pressure of Water Calculator is built to make science easy. You don’t need to flip through water vapor pressure charts or memorize equations. With this tool, you’ll get fast, accurate results at any temperature. Whether you’re working on a school project, lab research, or just geeking out, this app’s got your back.

FAQs

What is vapor pressure in simple words?

It’s the force of water turning into vapor.

Why does vapor pressure increase with temperature?

Heat gives molecules more energy, so more escape into the air.

What’s the vapor pressure of water at 100 °C?

At boiling point, it’s 101.3 kPa or 760 mmHg (1 atm).

Can I get vapor pressure in different units?

Yes, the calculator shows kPa, mmHg, atm, hPa, and psi.

Is this calculator free?

Absolutely. You can use it anytime, anywhere.