Humidity Calculator – Relative & Absolute Humidity
Calculate relative and absolute humidity from temperature and dew point
Table of Contents
How to Use
- Enter the current air temperature
- Enter the dew point temperature
- Select your preferred temperature unit (Celsius or Fahrenheit)
- Click calculate to see humidity results
What is Humidity?
Humidity refers to the amount of water vapor present in the air. It's a crucial meteorological parameter that affects comfort, weather patterns, and various industrial processes.
There are several ways to measure humidity, with relative humidity and absolute humidity being the most common.
Types of Humidity
Different humidity measurements serve different purposes:
- Relative Humidity (%): The ratio of current water vapor to the maximum possible at that temperature
- Absolute Humidity (g/m³): The actual mass of water vapor per unit volume of air
- Specific Humidity (g/kg): The mass of water vapor per unit mass of moist air
- Mixing Ratio (g/kg): The mass of water vapor per unit mass of dry air
- Dew Point: The temperature at which air becomes saturated and water vapor condenses
Applications
Humidity calculations are essential in many fields:
- HVAC systems design and optimization
- Weather forecasting and meteorology
- Agriculture and greenhouse management
- Industrial process control
- Museum and archive preservation
- Food storage and processing
- Pharmaceutical manufacturing
- Indoor air quality assessment
Frequently Asked Questions
- What is the difference between relative and absolute humidity?
- Relative humidity is a percentage showing how much water vapor is in the air compared to the maximum it could hold at that temperature. Absolute humidity is the actual mass of water vapor per unit volume, regardless of temperature.
- Why can't dew point be higher than temperature?
- Dew point is the temperature at which air becomes saturated with water vapor. If the dew point were higher than the current temperature, condensation would already be occurring, and the air would cool to the dew point temperature.
- What is a comfortable relative humidity level?
- For human comfort, relative humidity between 30-60% is generally considered ideal. Below 30% can cause dry skin and respiratory discomfort, while above 60% can feel muggy and promote mold growth.
- How does temperature affect relative humidity?
- As temperature increases, air can hold more water vapor, so relative humidity decreases even if the absolute amount of moisture stays the same. Conversely, cooling air increases relative humidity.