Wet Bulb and Humidity Ratio Calculator
Estimate liquid-water thermodynamic wet-bulb temperature, humidity ratio and moist-air enthalpy from T/RH/pressure.
YOUR CALCULATION
Result
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Calculation steps
Work through one step at a time or reveal the complete calculation. The steps use your current inputs.
How to calculate
Use the saturation relation to determine water content, then solve the adiabatic saturation energy balance with makeup liquid at wet-bulb temperature.
w=0.621945 e/(P−e); h=1.006T+w(2501+1.86T); solve saturated energy balance for Tw
Worked example
At 100% RH the wet-bulb temperature equals dry bulb. At 25°C, 50% RH and 101.325 kPa the humidity ratio is about 9.88 g/kg dry air.
Assumptions and input details
Approximate ideal moist air with fixed heat capacities and FAO saturation pressure. Limited to dry bulb 10–50°C, RH 20–100% and total pressure 80–110 kPa; wet bulb below 0°C is rejected. Not an instrument calibration, WBGT or heat-exposure assessment.
Unit definitions
Unit selection is independent of language. Each selector contains only units for its physical quantity. Calculations use defined base units internally.
Using this calculator
Can I enter my own problem?
Yes. Replace the example values with your own inputs. The result, calculation steps, tables and applicable diagrams update from those inputs. Blank or invalid values clear the result; example values are never silently substituted for missing inputs.
Are the results exact?
Results use floating-point arithmetic and displayed rounding. Read the formula, assumptions and any stated data precision before interpreting the result.
Is my input uploaded?
The calculation runs in your browser. No account, file upload or external AI service is required. Inputs are not saved between page reloads.
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