My fenix 6 measures a heart rate that’s way too high. Anyone else who has the same problem?

Moved thread to fenix 6 forum.

Yeah this happens.  You can get some really weird spikes.  It's kind of scary when you work out and see it jump to 180 when you know you are about 140.

Bought a forearm strap and the problem is solved, which admittedly, I shouldn't have to do.

Not another thread about heart rate, if you click the search option at the top & type heart rate you'll find more than enough posts.

I have exactly the same problem with my Fenix 6, sitting still it shows OK pulse readings, but when walking it over estimates my pulse with a factor 2-2.5.

I don't have a such issue but it throw high heart rate alert two times recently. And I'm sure my heart rate was just normal.

I've compared my new fenix 6 with my previous 645 forerunner which was accurate, and its 20-30 beats higher all of the time e when running, but not at rest. very frustrating & annoying as this obviously outs all the other metrics out, such as VO2, recovery rates , and as I have always trained to HR, makes this watch pointless for training & racing. 

High HR while running is not uncommon, and is known as "cadence lock" usually caused by the watch moving on your arm with each step, allowing external light to enter the sensor in a rhythmic way. The sensor picks up on this rhythm, rather than the changes in light in your arteries with each heart beat.

As a larger and heavier watch than the 645, the F6 can be more prone to movement than what you may be used to. Make sure the watch is positioned well away from the wrist bone on the fleshy part of the wrist, and the band is pretty snug - this ensures a better seal against external light entering the sensor. Personally I find I have to have the band 1-2 notches tighter for accurate HR while running than I do for 24/7 monitoring.

Yes, this. ^^

I switched from a FR 645 to Fenix 6 and the size and weight makes it move around on the wrist way more than the much lighter 645 does.

I found I had to wear the Fenix 6 higher up on the arm and tighter than the 645 for WHR to be accurate. Once that was done I found it working as well as the 645, which is not awesome, but good enough for easy runs.

Nowadays I mostly run with a Polar OH1+ on my arm. Reliable OHR every single time! For intervals (yeah, I wish, still recovering from injury) I use my HRM-Run strap.