Wildly wrong sleep data imported from Garmin Connect

"Sleep" metrics have sync'd over from my Garmin watch, but they're wildly wrong.

Here's a breakout for the past 4 days:
5/18: 7h23m Garmin, 9.55 Cron
5/17: 8h46m Garmin, 1.42 Cron*
5/16: 7h57m Garmin, 9.62 Cron*
5/15: 6h34m Garmin, 6.57 Cron*, **

*These were back-synced when I opened my Cronometer account
**This one's dead-on.

There doesn't seem to be any mapping or way that I can make sense of what's getting transferred, it's almost as though there's a data field mismatch -- i.e, some completely different piece of data is getting read as "sleep" & then rendered as a number of hours. I have my doubts about the accuracy of Garmin's sleep data, but this is clearly a data transfer error.

I understand I can simply omit the sleep data from sync, but this calls into question the accuracy of all the other data. I'd been hoping to pull data into Cronometer (as it's better-focused on the health metrics I care about most right now), but I'd rather not have to manually verify the data transfer every day. (And once transferred, it doesn't look like data can be removed - it's just wrong forever in one's Cronometer DB.)


  • Options

    I'm seeing the exact same issue.
    Also in May 2020.

  • Options

    Would you mind writing in to support@cronometer.com with a few details about dates and times reported in your Garmin app vs. Cronometer? Screenshots of your Garmin app would be a big help!

    Were there any interruptions in your sleep on those dates? Sleep data can be a bit trickier to import compared with other metrics because they are usually recorded over two different dates and then reported as a single value - it can cause issues that we wouldn't see with other imported data.

    Thanks for bringing this to our attention so that we can look into this further!


    Karen Stark
    As always, any and all postings here are covered by our T&Cs:

  • Options

    I'm not sure if this has been resolved or not, but I'm also seeing weird sleep data from my Garmin. Consistently Cronometer initially shows a higher number than Garmin does in Connect. However if I go back and open Connect to view the sleep data, then go back to Cronometer, it'll be refreshed with accurate data. The initial sync is pretty consistently incorrect.

    For today's data it looked like Cronometer was including the "Awake" time in the total sleep time. That may have been a coincidence though.

  • Options

    I was going to buy a Garmin device specifically for sleep tracking and syncing it with Cronometer. Thanks for the warning.

  • Options

    To be clear, in my case, the sleep data my Garmin collects seems to be correct. Or at least consistent and I have no reason to question it. It's the integration with Cronometer that seems to be the issue. Each morning I check my data in the Garmin app and it's consistent, at least in overall time, with the amount of sleep I got.

    The issue is what shows up in Cronometer. If Garmin says 6.5 hours, Cronometer (after the first sync) might show 10.25 hours. Then later in the AM it could say 8.5. Eventually sometimes it will end up being in the ballpark by the end of the day but I don't know why it would change. Other times it never corrects itself. The Garmin Connect data isn't changing once the day is recorded.

    I did reach out to Cronometer support and they were going to pass the information, along with screen captures, on to the dev team.

    While I would like Cronometer to accurately reflect what my Garmin measures, it's not a deal breaker for me at this time. Garmin Connect has it and I can see the trends I'm interested. I'm a big fan of the Garmin Fenix watches. And a big fan of Cronometer for what it does. Hopefully it'll be fixed at some point.

  • Options

    @BlueWind, thank you for explanation

  • Options

    I find several things to be true:

    • Garmin inconsistently records time I'm not wearing the watch that falls during my sleep hours as 'sleep time'.
    • Cronometer-synced sleep times are often but not always higher than the Garmin times, & rarely match exactly.
    • Cronometer-synced sleep times sometimes appear to be from the previous or following day.

    If I can figure out how to stop syncing just sleep time, I'll be doing that, because at this point it's just data-noise. When I remember to do so, I delete it. It's meaningless.

  • Options

    @na7 I have a Vivosmart 4 that syncs sleep and heartrate metric (as well as weight from my scale) to Cronometer. I've been using it for months without issue. Couldn't be happier with the integration. I'm not personally seeing any of the issues that @ericsscoles is.

  • Options

    Has there been a fix for this yet? I am having the same issues.

  • Options

    I am also having this issue using Garmin Instinct 2 Solar.

Sign In or Register to comment.