The slider explores examples; its ends are not targets or safety limits.
Dew point23.4 °F
Open with these inputsDew point calculator for runners
Dew point describes the amount of moisture in the air and helps explain why two days at the same temperature can feel different. Enter temperature and relative humidity to calculate dew point. Use it as one part of the weather picture. It is not wet-bulb globe temperature or a safe-exercise threshold.
Results update as you edit.
Your result, in detail.
Review the assumptions before turning a calculation into a target.
| Measure | Value |
|---|---|
| Dew point · US | 32.1 °F |
| Dew point · metric | 0.0 °C |
Worked comparison
How different can two equally warm mornings feel?
Read the dew point at three humidity levels while air temperature stays fixed. When checking your own forecast, enter the temperature and humidity from the same hour. Use the result as moisture context, not as a personal safety cutoff.
Relative humidity (%) Dew point
Edit a value below. Compare all three results as you go.
Relative humidity (%) Dew point
Edit a value below. Compare all three results as you go.
Why this number?
A tool from Breno Melo Endurance Coaching. Meet the coach.
How this is calculated
Magnus approximation: γ = ln(RH/100) + 17.625T/(243.04+T); dew point = 243.04γ/(17.625−γ), temperature in °C.
How do I use it?
Enter air temperature and relative humidity from the same weather observation.
US mode puts Fahrenheit first; both temperature systems are shown. Dew point describes moisture and is not a heat-safety threshold.
- Enter recent, representative values.
- Choose units and check the assumptions.
- Review the result and its context.
- Copy, share or print the output.
Public inputs are encoded in share links. Check what you are sharing.
Questions, answered.
How humid will this run feel?
Dew point describes the amount of moisture in the air and helps explain why two days at the same temperature can feel different. Enter temperature and relative humidity to calculate dew point. Use it as one part of the weather picture. It is not wet-bulb globe temperature or a safe-exercise threshold.
Is dew point the same as heat index?
No. Dew point describes atmospheric moisture. Heat index and wet-bulb globe temperature use different definitions and inputs.
Why do I need relative humidity?
Temperature and relative humidity determine the Magnus dew-point estimate. Relative humidity must be greater than zero and at most 100 percent.
What does the result assume?
Magnus approximation: γ = ln(RH/100) + 17.625T/(243.04+T); dew point = 243.04γ/(17.625−γ), temperature in °C.
Is this an exact prediction?
Arithmetic conversions are exact within input precision. Physiology models and planning scenarios are estimates; use the assumptions and your training response.
Can I change units or share this result?
Yes. Unit preference is remembered on this device. The share link includes calculator inputs; review them before sharing.
Do I need an email address?
No. Results, methodology and printable output are available without an email wall.
UNDERSTAND THE RESULT
Read the coaching context.
Use these guides to understand the assumptions and apply the result to your training.
