Summit Temperature Calculator
Fill in the values and the answer updates as you type.
How the Summit Temperature Calculator works
Air cools as it rises. Summit temperature = base temperature − lapse rate × elevation difference ÷ 1,000. The standard atmosphere uses 6.5 °C per 1,000 m. Dry air cools faster, near 9.8 °C, and moist or cloudy air cools more slowly, nearer 5 °C. Real mountain weather also depends on wind, inversions, and sun, so treat this as a starting estimate and check a mountain forecast. Example: with Temperature at base 18 °C, Base elevation 1200 m, and Summit elevation 3200 m, the result is Expected summit temperature (°C) = 5; Expected summit temperature (°F) = 41; Temperature change (°C) = -13.
Inputs and results
The Summit Temperature Calculator takes 4 inputs and gives 4 results.
What you enter
- Temperature at base (°C) — starts at 18.
- Base elevation (m) — starts at 1200.
- Summit elevation (m) — starts at 3200.
- Lapse rate (°C per 1,000 m) — starts at 6.5.
What you get
- Expected summit temperature (°C)
- Expected summit temperature (°F)
- Temperature change (°C)
- Elevation difference (m)
Example: Summit Temperature Calculator with the starting values
With temperature at base 18 °C, base elevation 1200 m, summit elevation 3200 m and lapse rate 6.5 °C per 1,000 m, the calculator returns:
| Expected summit temperature (°C) | 5 |
|---|---|
| Expected summit temperature (°F) | 41 |
| Temperature change (°C) | -13 |
| Elevation difference (m) | 2,000 |
Change any value above and the results update straight away.
Summit Temperature Calculator FAQ
How do I use the Summit Temperature Calculator?
Enter temperature at base, base elevation, summit elevation and lapse rate in the fields, then read expected summit temperature (°c), expected summit temperature (°f), temperature change (°c) and elevation difference (m) in the result panel. The answer updates as you type, and you can press Calculate or Enter to refresh it. Use “Copy link” to share your exact numbers with someone else.
What does the Summit Temperature Calculator calculate?
Expected temperature at the top of a climb from the base temperature. It returns expected summit temperature (°c), expected summit temperature (°f), temperature change (°c) and elevation difference (m) from the 4 values you provide.
What values does the Summit Temperature Calculator start with?
It opens with temperature at base 18 °C, base elevation 1200 m, summit elevation 3200 m and lapse rate 6.5 °C per 1,000 m so you can see a working result straight away. Replace them with your own numbers, or press Reset to return to these starting values.
Is the Summit Temperature Calculator free and private?
Yes. It is free, needs no account, and runs in your browser, so nothing you type is sent to or stored on our servers. See the Privacy Policy for details.
Can I rely on the Summit Temperature Calculator for important decisions?
Treat the result as a well-rounded estimate. Real situations often have details a general calculator cannot know, so confirm important decisions with a qualified professional. See the Disclaimer for more.