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Vapour Pressure of Water Calculator (Buck / Tetens Equation)

Calculate saturated water vapour pressure across temperatures from freezing to boiling with sub-0.1% meteorological precision.

Input Parameters

Instant Real-time Calculation

Water / Air Temperature (°C)

Result Chemistry

Saturation Vapor Pressure

-- kPa

Export calculation:

Calculation Logic:

Calculates saturated water vapour pressure using the internationally accepted Buck and Tetens equations for atmospheric and meteorological thermodynamics.

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Understanding Vapour Pressure of Water Calculator (Buck / Tetens Equation) & Formula

Mathematical Formula: P_sat (kPa) = 0.61121 × exp((17.67 × T) / (T + 243.5))

The Vapour Pressure of Water Calculator (Buck / Tetens Equation) on CalculatorScale.com is engineered to deliver instant, mathematically verified calculations conforming strictly to standard institutional equations. Whether planning long-term investments, managing household budgets, tracking clinical fitness targets, analyzing academic genetics, calculating veterinary dosages, or converting dimensional units, every calculation updates dynamically in real time without lag.

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Saturated Water Vapor Pressures Across Temperatures

Temperature (°C)	Vapor Pressure (kPa)	Vapor Pressure (mmHg)	Density of Saturated Vapor (g/m³)
0 °C (Freezing)	0.611 kPa	4.58 mmHg	4.85 g/m³
10 °C	1.228 kPa	9.21 mmHg	9.40 g/m³
20 °C (Room Temp)	2.338 kPa	17.54 mmHg	17.30 g/m³
37 °C (Body Temp)	6.274 kPa	47.07 mmHg	43.90 g/m³
100 °C (Boiling)	101.325 kPa	760.00 mmHg	598.0 g/m³

How to Use the Vapour Pressure of Water Calculator (Buck / Tetens Equation)

1 Input the temperature in degrees Celsius (°C).
2 Read the saturation vapor pressure in kPa and mmHg.

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