How Accurate is Blaze When Using GPS/Exercise Function

[TexasTommy]

I am training for a half marathon and hope Fitbit Blaze can help me train. When I go to exercise mode and use my phones GPS how accurate is distance traveled and pace? I have heard people say distance is off but I am not sure if that means when using GPS or not using GPS. For training purposes I need to make sure mileage and my pace are pretty accurate.... Thanks in advance.

[MakMak]

Hi, @TexasTommy! I've found that my GPS/walking distance is pretty spot on.

[bbarrera]

@TexasTommy Fitbit has admitted you may experience distance errors, and they have been working on a fix for months. The real issue is that like heart rate, it appears to be inconsistent, so you may have excellent distance accuracy one day and bad the next day. Some folks on the forum have dug deeper, and run a phone app like MapMyRun at the same time as Blaze. The phone app will have correct distance, but Blaze is wrong. Again it doesn't happen for everyone, or every run, which makes it even more frustrating if you are training for a big event. Nothing is perfect, however for training I would recommend checking out a dedicated GPS running watch: http://www.dcrainmaker.com/2015/11/winter-sports-gadget-recommendations.html

[J-flex]

I have a Blaze and find my distance with GPS is accurate

[MakMak]

Thanks for the feedback @bbarrera! I'm guessing if it's an incosistent gremlin it's really difficult to track down the issue.

[bbarrera]

the funny thing is that the early phone apps like Runkeeper had the same problem with mileage accuracy back in 2008-2009, and its long since resolved and forgotten. The HR accuracy issue is different, there are a few optical wrist and upper arm HRMs that are quite good, the rest of the pack isn't there yet. I do a lot of heart rate based interval training on the bike, where accuracy is important, and so I still use a chest strap.

[Rich_Laue]

I've tried the Surge., connected Blaze, the Fitbit app, charity miles, mapmywalk, map my exersice, A fitness, the OS tracking of the phone, and Strava. Funny thing is that on a 10 mile walk, there is no agreement in distance. 

[bbarrera]

I'm seeing much better accuracy between my devices and AW connected GPS. The exception is Fitbit Blaze.

This year I have 141 bike rides and over 3100 miles. The majority of rides have been tracked with:

- Apple Watch using connected GPS (iPhone 5s)

- RideWithGPS app running on iPhone 5s

- Garmin Edge 520 GPS bike computer

The mileage for all the rides are within 1% of each other, and often within 0.5% of each other.

The Blaze mileage for rides is not always accurate. I'm not alone on Blaze mileage accuracy issue. On these forums there are widespread reports from walkers, runners, and bikers that mileage is not correct, from 5-10% and even a few reports of 20-30% inaccuracy. Apple Watch version of connected GPS is accurate, and mobile app like RideWithGPS is also within 1% of external bike computer GPS, so the Blaze accuracy issue is a Fitbit problem. Its been acknowledged months ago by Fitbit moderators, and reportedly being worked on.

[shipo]

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@TexasTommy wrote:

I am training for a half marathon and hope Fitbit Blaze can help me train. When I go to exercise mode and use my phones GPS how accurate is distance traveled and pace? I have heard people say distance is off but I am not sure if that means when using GPS or not using GPS. For training purposes I need to make sure mileage and my pace are pretty accurate.... Thanks in advance.

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I'm training for a few races this year (a very hilly 10-miler, and the Ragnar Reach the Beach relay, plus a few 5Ks) and do my training runs with a few folks with Fitbit Blaze and Fitbit Charge HR (both of which use a smart phone tethered GPS), and I use a Fitbit Surge.  As a general rule we all end our runs (which typically range from ~5-miles to ~15-miles) with the reported distance showing within a tenth of a mile or two.

Upon occasion one or more of the trackers will get the results wrong, sometimes really wrong; I would say my Surge is the most accurate, but even then it can be wrong and the Blaze can be correct; you just never know.

[TexasTommy]

Thanks for all the answers.

[3StarMom]

I am starting to think I should have invested in the Apple Watch.

[shipo]

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@3StarMom wrote:
I am starting to think I should have invested in the Apple Watch.

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I haven't seen any evidence which suggests the Apple Watch is any more accurate than the Blaze; do you have some infomation which says otherwise?

[3StarMom]

Yes I have tested my husbands Apple Watch, the Ihealth app, the Fitbit App, my Fitbit Alta, and now my Fitbit Blaze. The Apple Watch is consistent with the Ihealth App, the Fitbit app and all of the products I own seem to be hit or miss. But never consistent. Same walk, different day, different distance. That's my proof. But thanks for asking.

Sent from my iPhone

[bbarrera]

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@shipo wrote:

I haven't seen any evidence which suggests the Apple Watch is any more accurate than the Blaze; do you have some infomation which says otherwise?

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Look up ^ I'll repeat it for you:

This year I have 141 bike rides and over 3100 miles. The majority of rides have been tracked with:

- Apple Watch using connected GPS (iPhone 5s)

- RideWithGPS app running on iPhone 5s

- Garmin Edge 520 GPS bike computer

The mileage for all the rides are within 1% of each other, and often within 0.5% of each other. The Blaze mileage for rides is not always accurate, and someone took time to document that inaccurate Blaze mileage is suddenly accurate when sync'd to Strava.

I'm not saying its a universal problem, but it is happening.

[3StarMom]

I am a little confused as to why you are arguing this issue. You said yourself the items you are using are within .5% and 1% accuracy. Which I am agreeing with based on my EXPERIENCE using an Apple Watch with an IPhone. But no where did you say you are using a Fitbit Blaze and the Fitbit App. Which is what I am comparing too. Unless it was in the original post, But I didn't see it in your three tracking apps or devices you just stated. As with your statement, my statement was made with trial and error, testing the same way it sounds like you are testing yours. Through actual experience.

Sent from my iPhone

Sent from my iPhone

[shipo]

@bbarrera, your anecdotal evidence is pretty much irrelevant; I mean seriously, only 3,100 miles this year? Let me frame it for you, in the summer if 1974 I rode my bicycle 4,025 miles in 35 days, that and I've run in excess of 3,100 miles in a year twice since I turned 50, a heck of a lot rigorous than only 3,100 cycling miles in a year.

If you really want to get into it, I'll be happy to; the fact is, you seem to like to dump on my posts and it is time for you to stop.

[OleMarius]

Every time I'm out jogging with gps on with my phone connected to the blaze my rute is off by 6-8 km. Like I got a 8,5 km rute, tho its logging as 16 km.

It is as incorrect logging that you could get

[Rich_Laue]

Which mode on the tracker do you use RT the run mode

[winterdawn]

Me too. My brother has one and When him I and I walk there is a huge differnece between the fitbit and apple watch. We know we walk 8 miles cause we walk on trail that is 8 miles long. His watch will say he walked 8.01 miles. My fit will say I haven't even walked 7.5 miles. Yes I have set my stride also. The more I read baout fitbits issues the more I am leaning towards the apple watch. It sucks when you pay 200 bucks for something and it doesnt wok correctly.