Anyone know how to improve the accuracy of the accumulated elevation gain on my Garmin Edge 1000? I know a variety of algorithms are used in different devices, but my Garmin seems to consistently be about 30% low.

Thanks,
Mark W

30% low compared to what? the garmins use barometric preasure so if you have a big temp change durig a ride it can be thrown off some also.

Compared to other riders on the same ride--my garmin consistently registers less elevation gain. Today's ride had a moderate change of temperature (45 to 75 deg), but a friend on the same ride recorded 3412 ft of gain compared to my 2592. He uses a similar garmin 1000.

there is a function to enable elevation correction in garmin connect.. try it and see what happens. Maybe you buddy is enabling it or vice versa

Using the Garmin Connect correction, it changed my elevation gain by 6 ft, so not much difference.

I'm guessing the 1000 has the ability to input known elevation points? My 500 does. You can find the location of the NGS Benchmarks and input precise elevation points into the Garmin (find the point on the website, , or the better-than-nothing option, use the What is my elevation website to put in your approximate elevation. This helped quite a bit with my 500, as I found that on out and back routes, I was always descending markedly less than I was climbing or vice-versa.

That correction in Gamin connect is intended for devices without barometers.

This doesn't change the elevation gain/loss (the difference in elevation). It only affects the absolute elevation , which not many cyclists are interested in.

Not true. Pressure altimeters in Garmin units are subject to drift. What altitude correction does is adjusts the altimeter's data by matching it up to topographic data in the website's map database along the route. You might see this on a ride where you return to where you started and the raw data shows different elevations at the start and end of the ride. Applying correction will remove this error.

It's off by default for units with barometers.

It really exists for units which only use GPS for elevation (which is inaccurate).

There is no indication that it's useful for "drift" at all.

If drift was a general problem and the correction was useful in fixing it, it would not be off by default (it would be on by default).

People are naively thinking that something called a "correction" is always good. In this case, it makes the GPS data better and the barometeric data worse.

Understanding Sport Device GPS Elevation Issues | DC Rainmaker

(Note that dcrainmaker talking about getting accurate elevation for units without barometers.)

I found this pretty interesting.

GPS Elevation Accuracy Test: Smartphone Apps vs. Dedicated GPS | Singletracks Mountain Bike News

My out-and-back yesterday resulted in a net elevation change of 10 ft, and that was most likely due to the fact I didn't start my watch until a few seconds into the ride.

I have the forerunner 910xt with a barometer. (No elevation correction.) I did notice that it was reading 80 feet higher than one of the signs at the top of one of the peaks, but that could have been just a high pressure system blowing in.

https://connect.garmin.com/modern/activity/1111162267

Have you looked up what the elevation change SHOULD have been for that ride using an actual map?

You shouldn't give advice on things you don't understand.

Do you realize your link is six years old??? For best results it recommends using out of date hardware that isn't being made anymore.

When I did Washington Pass from Mazama, my Garmin Fenix 3 watch recorded 3,369 feet of elevation gain. According to the best topo maps, the correct value is 3,374 feet.

EDIT: My Edge 800 recorded 3,358 feet. Both are pretty impressive but the watch did a slightly better job than the cyclocomputer. Which is consistent with my experience with both devices. On that particular day, you would expect a barometeric altimeter to slightly underestimate elevation gain due to the temperature.

That information still applies.

It's still disabled for devices without barometers.

Do you realize that you should find a newer link that says people should use it?

My Garmin Touring (no barometer) generally shows about 20% less total elevation than I get when I upload the same ride to ridewithgps. Don't know which is accurate, maybe neither.

No, it's intended for use with data that needs correction. It's automatically run on devices that aren't labeled as having a barometer.

I hope you're capable of understanding the distinction.