What is it?
The Dew Point Calculator shows the temperature at which the air becomes so damp that dew or mist forms. From the temperature and humidity it also tells you how the air feels and how much water it holds.
Who is it for?
People dealing with damp walls and mould, painters and waterproofing workers, and weather enthusiasts.
How to use it
Enter the Air temperature and Relative humidity (%). The answer appears as you type; there is no Calculate button. Tap Copy result to copy it, or Share on WhatsApp to send it.
What dew point means
The dew point is the temperature at which the air becomes saturated and dew or condensation forms (Magnus formula). Unlike relative humidity, it tells you how much moisture is really in the air.
Comfort guide
- Below 10 °C: dry and comfortable.
- 10–16 °C: comfortable. 16–20 °C: a bit humid.
- Above 21 °C: muggy and sticky, as in Mumbai or Kolkata in monsoon. Above 24 °C: oppressive.
Condensation and mould
- Any surface colder than the dew point gets wet: AC ducts, cold water pipes, windows in winter, walls behind wardrobes.
- Keep surfaces warmer, improve ventilation, or lower humidity with a dehumidifier or AC.
- Paint and waterproofing work also need surfaces above the dew point to dry properly.
Worked example
30 °C at 70% humidity gives a dew point of about 24 °C: very muggy. A glass of water from the fridge at 8 °C will sweat immediately.
Errors and how to fix them
- “Humidity is between 1 and 100%”
Open the tool: Dew Point Calculator
Still stuck?
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Questions, or an error not listed here?
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