Garmin Forerunner 645 – Available Now

Garmin’s best-kept secret is available now.

The Garmin Forerunner 645 is also available as an optional MUSIC version, the 645m.


  • It looks to have everything a running watch could ever ‘need’. Some of the functionality like contactless payments and music will take a few weeks/months to properly roll out.
  • Personally I would prefer a sports watch appearance, but Garmin have probably made the right call with this design for the broader target market of runners
  • It’s expensive BUT the onboard MUSIC could make this a ‘Kerching moment’ for Garmin’s accountants as it’s the only high-end running watch with MUSIC. (Polar M600 is awesome but mid-range)
  • The Forerunner 645 is clearly different in functionality from other Garmins in the Forerunner range.


The Forerunner 645 has notably more functionality than the 630 and 235 although on pure ‘competitive’ running features the 630 and 645 are similar. You might have to think about justifying your upgrade from your 630 but the upgrade from the 235 is a much easier call with many obvious differences. If you don’t do multisports then there is no real reason to go for the 935/Fenix 5 alternatives (discussed in this post; link to: For customers, the big pull of new stuff in the 645 will come from ONBOARD MUSIC and GARMIN PAY, both will be highly desirable features for MANY casual to serious runners.

  • New format compared to style of the Forerunner 630 / 235
  • Strong glass yet overall ‘lightweight’ form
  • Standard bands
  • Improved screen resolution at 240x240px, but this still lacks behind smart watches and most Suunto Spartan models.
  • It looks like the touchscreen from the 630 is no more – but that is NOT confirmed.
  • Battery life looks low. But without MUSIC playing it will be up to 12 hours.
  • Lots of connectivity – probably every key function
  • Music with c800 onboard songs and Bluetooth headphone connectivity
  • Garmin Pay (contactless effectively won’t be widely avaialble until 2018)
  • It’s a cycling watch BUT it will NOT support your power meter
  • It’s a pool swim watch BUT will not cache underwater HR from HRM-TRI. Not really designed for open water use with restricted functionality there.
  • It’s not a triathlon watch ie it does not have multi-sport profiles
  • It has all the activity tracking functionality.
  • Supports both BLE and ANT+ sensors
  • Has all the clever Firstbeat physiological functionality
  • Will support CIQ 2.4 – so you will get access to any new apps as they are made available
  • ‘Obviously’ it will support Garmin’s Running Power


For a detailed look on how it compares to the other RUNNING forerunners take a look here:

Garmin Forerunner 645 Specs (Detailed) – Comparison to FR 630 and FR 235


And for a look at how it compares to the high-end tri watches take a look at this.

▷ Garmin Forerunner 645 Specs | Detailed Comparison To 735XT and 935




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15 thoughts on “Garmin Forerunner 645 – Available Now

  1. you mention ‘Not really designed for open water use with restricted functionality there.’….can you elaborate on restricted functionality….all I would require is time and distance.

  2. The real challenge with openwater swimming is getting a good GPS track when the watch is most of the time submerged in water. Some watches with dedicated openwater swimming mode have fancy algorithms to compensate for that. The 645 doesn’t do that, meaning that accuracy will be severely degraded when worn on the wrist.

  3. @the5krunner: Are you sure about the BLE headphones connectivity? I believe it’s regular Bluetooth for headphones, not BLE.

  4. As a matter of interest anyone know when is this thing going to be available? Friend of mine is going to the US in two weeks so thinking it’s a no-brainer to get them to pick up the music version for me there as it’s cheaper than even the non-music one here.

      1. Oh well no shiny new toy for me this time so 🙁 Gives me more time to keep saving the cents I guess.

  5. Will the NON Music version have significantly better battery life and will it also include Garmin Pay?

    1. Smartwatch Mode: Up to 7 days

      GPS mode without music: Up to 12 hours

      GPS mode with music: Up to 5 hours

      ie 7 hours difference but only if playing music is taken into account

      yes they both have PAY

      1. Thanks. Still do not get the appeal of having the music version. Do most people run without a phone?? Plus who wants to load music on their watch all the time like the iPod shuffle days? Streaming is where its at.

      2. yep streaming must be the longterm trend.
        i run in a busy park near home. less than half the people i pass run to music. most of those running to music are women (80%). i guess maybe 80% of those listening to music do it through a phone.

        IF i didn’t do this site and IF I wanted to listen to music then i would want it all on one device.

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