Dew Point Calculator

Calculate dew point temperature from air temperature and relative humidity. Estimate humidity comfort, condensation risk, moisture level, vapor pressure, temperature-dew point spread, and weather comfort for outdoor work, gardening, hiking, camping, livestock checks, greenhouses, and home humidity planning.

Calculate Dew Point

Dew Point uses air temperature and relative humidity to estimate when moisture condenses.
Your result will appear here.

How the dew point calculator works

Dew point from humidity:
The calculator converts your temperature to Celsius, applies the Magnus approximation, and converts the dew point back to your selected unit.

Comfort / moisture level:
The calculator compares the dew point to common comfort ranges to estimate whether the air feels dry, comfortable, humid, or very muggy.

Condensation risk:
Enter a surface temperature to check whether condensation is likely on windows, walls, pipes, plants, glass, or outdoor surfaces.

Target dew point:
Enter a target dew point and the calculator estimates the relative humidity needed at the current air temperature.

Why use a dew point calculator?

A dew point calculator helps understand moisture in the air better than relative humidity alone because dew point is tied to how much water vapor is actually present.

It can be useful for weather comfort, greenhouse humidity, gardening, condensation prevention, mold risk checks, camping, hiking, livestock care, home humidity, and outdoor work planning.

What your result means

Your result shows dew point temperature, temperature-dew point spread, comfort category, condensation risk, surface temperature comparison, estimated vapor pressure, comparison humidity result, and target humidity estimate. These are planning estimates based on temperature and relative humidity.

Dew point formulas

Frequently asked questions

What is dew point?

Dew point is the temperature at which air becomes saturated with water vapor and moisture can begin to condense.

How do you calculate dew point?

Dew point can be estimated from air temperature and relative humidity using the Magnus approximation.

Is dew point better than humidity?

Dew point often gives a better sense of how humid or muggy it feels because it reflects the actual moisture content of the air.

When does condensation happen?

Condensation can happen when a surface temperature is at or below the dew point temperature of the surrounding air.