Measurement tool
Altitude Meter.
GPS elevation above sea level in meters and feet — plus estimated air pressure, water boiling point, and terrain category.
Uses your GPS coordinates to look up ground elevation from a terrain database — the same method used by dedicated altitude sites for reliable readings.
Needs GPS location access
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Elevation
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— ft
Data Source
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90m terrain DEM
Air Pressure
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hPa (estimated)
Boiling Point
—
°C water boils
Coordinates
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Frequently asked questions.
How accurate is GPS altitude?
GPS altitude accuracy is typically ±10–30 meters under open sky. It's less accurate than horizontal GPS position because GPS satellites orbit in a plane that makes vertical measurements harder. The accuracy field shows what your device GPS reports.
Why does air pressure decrease at altitude?
The weight of the atmosphere above you decreases as you climb. The International Standard Atmosphere model calculates that pressure drops by roughly 12 hPa per 100 meters near sea level.
Why does water boil at lower temperatures at altitude?
Boiling occurs when water's vapour pressure equals atmospheric pressure. Lower atmospheric pressure at altitude means less energy is needed to vaporize water, so it boils at lower temperatures. At 3,000 m water boils around 90°C instead of 100°C.
What is altitude vs elevation?
Technically, elevation is height above sea level measured on the ground, while altitude usually refers to height above the ground (e.g., an aircraft). For our purposes on the surface, we use both terms interchangeably to mean metres above mean sea level.