Estimate temperature shifts across wide changing altitude levels. Compare pressure, density, and lapse rate effects. Plan physics, aviation, and mountain weather conditions with confidence.
Temperature: T₂ = T₁ - L × (h₂ - h₁). Here, L is the lapse rate in °C per meter.
Pressure with lapse rate: P₂ = P₁ × (T₂ / T₁)^(g / (R × L)). Temperatures use Kelvin.
Isothermal pressure: P₂ = P₁ × e^[-g(h₂-h₁)/(RT)]. This applies when the lapse rate is zero.
Density: ρ = P / (R × T). Humidity correction separates dry air pressure and water vapor pressure.
Density altitude: DA ≈ PA + 120 × (OAT - ISA). This gives a useful aviation estimate in feet.
| Altitude | Approx Temperature | Typical Pressure | Use Case |
|---|---|---|---|
| 0 m | 15.0 °C | 1013.25 hPa | Sea level standard reference |
| 1000 m | 8.5 °C | About 899 hPa | Hill weather estimate |
| 2000 m | 2.0 °C | About 795 hPa | Mountain hiking check |
| 3000 m | -4.5 °C | About 701 hPa | High altitude planning |
| 4000 m | -11.0 °C | About 616 hPa | Aviation and climbing review |
Air temperature often falls as altitude rises. The main reason is pressure. Higher air expands because surrounding pressure is lower. Expanding air uses internal energy. That process cools the air. The usual standard lapse rate is 6.5 °C per kilometer. Real weather can differ from this value. Clouds, wind, sunlight, terrain, and humidity can change the actual temperature.
Pressure also falls with height. There is less air above you at higher elevation. Lower pressure reduces air density. This affects breathing, aircraft performance, engine power, boiling water, and sound speed. The calculator estimates pressure with a lapse-rate atmosphere model. It also supports an isothermal case when the lapse rate is set to zero.
Air density depends on pressure, temperature, and water vapor. Warm air is usually less dense than cold air. Moist air is also less dense than dry air at the same pressure and temperature. That surprises many users. Water vapor has a lower gas constant effect than dry air. This tool includes a humidity correction for better density estimates.
This calculator is useful for aviation, mountain trips, weather lessons, and lab work. Pilots can compare pressure altitude and density altitude. Hikers can estimate colder summit conditions. Students can see how lapse rate affects temperature and pressure together. Engineers can review air density for fans, engines, and cooling systems.
The target temperature is based on the base temperature, height difference, and lapse rate. The pressure result follows the barometric relationship. Density uses the ideal gas law. The graph shows how temperature and pressure change between the two altitude points. Use local weather reports for final safety decisions.
It estimates air temperature, pressure, and density at a target altitude. It uses base weather values, altitude difference, and lapse rate. It is useful for physics study, hiking, aviation planning, and weather comparisons.
A common standard value is 6.5 °C per kilometer. Use a local forecast lapse rate when available. Real air can warm, cool, or invert depending on clouds, wind, humidity, and terrain.
Pressure falls because there is less air above you at higher elevation. The weight of the air column becomes smaller. That lower pressure also changes air density and boiling point.
No. It is a physics estimate. Real weather can change quickly. Local temperature, wind, terrain, clouds, and humidity may cause differences. Use official weather data for safety decisions.
Density altitude is the altitude where standard air has the same density as current air. High density altitude reduces aircraft performance, engine power, and propeller efficiency. Hot, high, and humid conditions raise it.
Moist air is less dense than dry air at the same temperature and pressure. Water vapor changes the gas mixture. This calculator separates dry air pressure and vapor pressure for a better estimate.
Yes. Enter a desired temperature in the optional field. The tool uses the lapse rate and base temperature to estimate the altitude where that temperature may occur.
Water boils at lower temperatures when pressure falls. Higher altitudes usually have lower pressure. The boiling point result helps explain cooking changes and pressure effects in mountain regions.
Important Note: All the Calculators listed in this site are for educational purpose only and we do not guarentee the accuracy of results. Please do consult with other sources as well.