The elevation of a place comes from a terrain model, a map that stores the height of the ground every few feet. In the US, the USGS 3D Elevation Program (3DEP) has a height every 10 meters (about 33 feet) across the lower 48, and much finer where it’s been flown with lidar. Google Maps doesn’t give you the number directly, but it does draw contour lines; Google Earth shows it when you hover the cursor; and on Mapsfera you get it in feet with one tap. What you shouldn’t trust is your phone’s GPS: it’s the fastest way to be off by 30 or 60 feet.
With Google Maps: the Terrain layer
Google Maps doesn’t show the elevation of a point, but on a computer it can draw the landscape with contour lines:
- Open Google Maps in your browser.
- At the bottom left, hover over “Layers” and click “More”.
- Select “Terrain”.
- Zoom in on the area. Contour lines appear, with the elevation in gray numbers on them.
To get the elevation of your spot, see which two lines it falls between: if it’s between the 800 and the 850 line, its elevation is between those two numbers. That’s a decent estimate out on a trail, but it isn’t an exact figure, and in cities the lines are hard to see. In the phone app, the layers button is at the top right; Google’s help doesn’t describe the terrain layer there, so if you can’t find it, use a computer.
With Google Earth: the elevation under your cursor
Google Earth runs in your browser and does give you the number: place your cursor on a point and its elevation appears at the bottom right. What it won’t do is subtract: it can’t give you the elevation difference between two points. For that, see the profile further down.
On Mapsfera: the elevation in feet
In Elevation finder you search for a place or tap the map and it gives you its elevation above sea level, in feet or meters. You can mark several points and compare them. In the US it reads a terrain model built from the USGS 3DEP data (10-meter resolution); elsewhere, from the best public source for each area.
For the elevation of where you are right now, use What is my elevation?: it takes your position from your phone, but reads the elevation from the terrain model, not from GPS.
Why your phone’s GPS gets elevation wrong
According to the US government, which runs GPS, a smartphone under open sky is typically accurate to within about 16 feet (4.9 m) horizontally. Vertically the error is larger, because all the satellites are above you and the geometry helps less. Between buildings, in a canyon or under trees, the error grows a lot. Some phones also have a barometer, which measures air pressure; it’s very sensitive, but pressure changes with the weather, so it needs calibrating.
A terrain model doesn’t have that problem: it’s built from airborne lidar and imagery, and it always returns the same number for the same spot. Its limit is different: it gives the height of the ground, so it doesn’t know if you’re on the tenth floor or on top of a tower.
Examples with numbers
Elevations of some well-known places in the US:
| Place | Elevation | Note |
|---|---|---|
| Denali, Alaska | 20,310 ft | Highest point in North America (2015 survey) |
| Mount Whitney, California | 14,505 ft | Highest point in the lower 48 |
| Leadville, Colorado | about 10,150 ft | Usually cited as the highest incorporated city |
| Colorado State Capitol, Denver | 5,280 ft | One of the west steps is marked “one mile above sea level” |
| Badwater Basin, California | −282 ft | Lowest point in North America, in Death Valley |
Mount Whitney and Badwater Basin are less than 85 miles apart: more than 14,700 feet of difference between the highest and the lowest points of the lower 48.
Open the three places from the example on Mapsfera and you get Mount Whitney at about 14,475 ft, Badwater Basin at about −266 ft and the Capitol steps at 5,278 ft. The Capitol lands within 2 feet of its marker. The summit and the salt flat come out a little short, and that’s expected: the terrain model stores one height for each 10 × 10 meter cell, so on a sharp peak or a tiny low spot the cell averages out the extreme. On ordinary ground, like a town or a backyard, the difference is a few feet at most.
Also notice that a city doesn’t have a single elevation. Denver’s neighborhoods vary by hundreds of feet. A city’s “official” elevation is the one of a reference point, usually downtown.
Elevation, altitude, height
- Elevation: height of the ground above sea level. In the US, measured from the NAVD 88 vertical datum.
- Altitude: usually used for things in the air, like an airplane above sea level.
- Height: measured from the ground up. A building has a height; its roof has an elevation.
- Elevation gain: the total climbing along a route, adding up every uphill stretch.
If you want the elevation gain of a route
To see how much a trail climbs and drops, draw it in the elevation profile and you get the elevation chart, the total gain and loss, and the steepest grades. If you already have the route as a GPX file from Strava, AllTrails or a Garmin watch, upload it to the GPX route profile. And if you want to know how far you can see from a summit, the distance to the horizon calculator does the math.