Specific Humidity Calculator

Specific Humidity Calculator calculator can be used to calculate the specific humidity of moist air based on temperature and relative humidity.

Input Parameters

Calculation Results

Calculation Formula

Specific Humidity (ω) = 0.622 * (Pv / (P - Pv))

Where:
ω = Specific Humidity (kg/kg)
Pv = Vapor Pressure (kPa)
P = Total Pressure (kPa, assumed to be 101.325 kPa for standard conditions)

Results

Vapor Pressure (Pv):

0.00 kPa

Specific Humidity (ω):

0.00 kg/kg

Specific Humidity Calculator Calculator Usage Guide

Learn how to use the Specific Humidity Calculator calculator and its working principles

How to Use the Calculator

  1. Enter the temperature of the moist air in degrees Celsius (°C).
  2. Enter the relative humidity of the moist air as a percentage (%).
  3. Click the "Calculate" button to compute the specific humidity and vapor pressure.
  4. The results will be displayed in kilograms per kilogram (kg/kg) for specific humidity and kilopascals (kPa) for vapor pressure.

Working Principle

The Specific Humidity Calculator uses the Magnus formula to estimate the saturation vapor pressure (es) based on the input temperature. The actual vapor pressure (Pv) is then calculated by multiplying the saturation vapor pressure by the relative humidity. Finally, the specific humidity (ω) is calculated using the formula:

ω = 0.622 * (Pv / (P - Pv))

Where:

  • ω = Specific Humidity (kg/kg)
  • Pv = Vapor Pressure (kPa)
  • P = Total Pressure (kPa, assumed to be 101.325 kPa for standard conditions)

Applications

Specific humidity is an important parameter in meteorology and engineering, used to understand the moisture content of air. It is particularly useful in HVAC systems, weather forecasting, and environmental studies.