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In looking at the Garmin FR 645, the two closest competitor watches are definitely the Garmin 935 and Garmin 630. You can think of the Garmin 645 as basically an upgraded Garmin FR 630 or a running-focused Garmin FR 935. It has the slim, compact body of the 630, but with some of the modern features on the 935. Toward the bottom of this post, we have a chart where you can see differences in specs, but for now we’ll focus on the major reasons you’d get each device.
Garmin 645 vs 935 vs 630 – Music Storage is HUGE
The Garmin FR645 is available in two different configurations. You have the Garmin 645 Music, which has native storage for music, and the Garmin 645, which is the standard unit. The 645 starts at $400 [check price on Amazon] while the 645 Music starts at $450 [check price on Amazon]. The watches are the exact same beyond music storage and the implications music playback will have on battery life.
Neither the Forerunner 935 nor the Forerunner 630 has internal storage for music play, which means while you can control the music playing on your phone, you cannot go for a phone-free workout and still have your music. With the Forerunner 645 Music, you can take the watch and Bluetooth headphones… that’s all you need. Interestingly enough, there are two options for music storage with the 645. You can load on your personal music, as the 645 can support up to 500 songs, or you can sign up for iHeartRadio All Access and download select playlists and stations for use on the 645. iHeartRadio All Access starts at $10 per month, but I still think this will be the most likely way people will utilize the music storage feature.
If you were wondering how you access the music once it’s on the watch, below is a video from Garmin that explains this. It’s pretty simple. You just hold the “Down” button and it pulls up a music menu. And one thing that’s nice is that the 645 uses buttons (not a touchscreen), so it will be easier to fiddle with music when you’re working out or running. Additionally, according to Garmin’s website, the 645 Music is compatible with a fairly large list of headphones, including the Jaybird X3 and others.
Garmin Pay on Forerunner 645
As of this post, the FR645, FR645, and VA3 are the only Garmin devices to support Garmin Pay. If you aren’t familiar with Garmin Pay, essentially it’s Garmin’s version of Apple Pay. You can load select debit and credit cards from select banks onto your watch so that you can pay for goods and services on-the-go, directly from your wrist. Here’s a short list of supported banks, but you can check Garmin’s website for the full list.
Bank of America
MasterCard & Visa
Mastercard & Visa
Mastercard & Visa
Mastercard & Visa
First Tech Federal Credit Union
Peoples National Bank of Kewanee
Security Service Federal Credit Union
State Employees’ Credit Union
My hunch is that Garmin Pay will not be a deciding factor for a lot of people. It’s still very new and it is only supported at vendors that have contactless payment terminals. Therefore—like Fitbit Pay, Apply Pay, and Android Pay—it lags behind Samsung Pay in the number of locations where you can actually transact payments. This is because Garmin, Fitbit, Apple, and Android use NFC chips that are only compatible with those contactless payment terminals.
Samsung Pay, on the other hand, will work with most point-of-sale systems, including magnetic stripe and EMV (Europay, MasterCard, Visa) terminals for cards that have a chip inside. This is not a criticism of Garmin Pay because it is a nice feature to have, but you’ll still be somewhat insecure with where you can use your FR645 to make purchases. With that said, the number of NFC payment terminals is growing, so at least the trends are in your favor. Here’s Garmin’s original video showing you how to setup Garmin Pay (on the vivoactive 3).
Garmin Forerunner 645 vs 630 – Swimming, HRM & More
Let’s ignore the 935 for this part. The FR645 can track indoor (or pool) swimming, while the 630 is setup to be a running watch primarily. As such, there are a limited number of sports beyond running that you’d do on the 630. The FR645 will track distance, stroke count, stroke rate, SWOLF and more.
Garmin’s Elevate HR sensor on the 645. Same HRM as is on the 935.
The 645 also adds Garmin’s Elevate wrist HRM, which the 630 lacks. In fact, it was sort of puzzling when Garmin first announced the 630 since they added a WHRM to the FR235, which came out at the same time. I was expecting the 630 to also have the HR sensor. Despite the lack of a wrist HRM, however, the 630 (and 645) pair with Garmin ANT+ HRMs, including the HRM-Run. The 645, however, can pair with Bluetooth sensors as well, so there is a larger number of sensors that are technically compatible with the 645 (and 935) than are compatible with the 630.
Garmin 645 Watch Bands
Like the Garmin vivoactive 3, the 645 uses standard 20mm watch straps. That means you can get bands pretty much anywhere, allowing you to dress the watch up or down depending on the occasion. Both the 935 and 630 have replaceable watch bands, but they require a screwdriver and are not as widely available as the 20mm bands of the 645.
Garmin Forerunner 645 vs 630 vs 935 Review Chart
$400 for standard version - $450 for music version
Think of the 935 as the ‘Fenix 5 Lite’ in that it is a lighter, more streamlined version of the Garmin fenix 5. It is a multi-sport triathlon watch and even has a golf app built in.
Garmin Forerunner 935 vs 645 – Triathlons
Let’s ignore the 630 for now. The chief advantage the 935 has over the 645 is that it can support open-water swimming and triathlons. The 645 can only track indoor swimming. Anyone that’s interested in participating in triathlons should therefore look primarily at the 935 (or Forerunner 920XT, 735XT, fenix 3 HR, fenix 5X, fenix 5, or fenix 5S). The 645 is still mostly a runner’s watch.
Garmin Forerunner 935 vs 645 – Battery Life
If you just look at the spec sheet, the 935 clearly has the better battery life. Garmin says it can get up to 2 weeks in smartwatch mode and up to 24 hours in GPS mode with the heart rate sensor running. This made a lot of triathlons and Ironman participants very happy since the 735XT didn’t quite have enough juice overall. Compare that to the 645, which is stated at up to 7 days in smartwatch mode (likely 4-5 days with moderate use) and up to 5 hours in GPS mode with the HR going and music playing.
Of course, you’re getting the extra music feature with the 645, but still, battery life is better on the 935.
Garmin FR935 Supports HR During Swimming
Since the 935 can be paired with the HRM-Tri and HRM-Swim, it can also gather HR data during swimming workouts. According to Garmin’s website, the 645 is not compatible with either of those HRMs.
While the Forerunner 630 has been out for a number of years now, it still has a lot going for it. It is a high end running watch with all the activity/sleep tracking features that you expect from newer Garmin watches. It also has smart features, including the ability to display incoming phone notifications.
Garmin Forerunner 630 vs 645 – Price!
I won’t even waste your time comparing the 630 to the 935. The biggest advantage the 630 has over the 645 is price. While its MSRP is $400, you can find it on Amazon for around $260 nearly everyday. So, it’s basically $200 cheaper than the 645. If you’re just looking for a solid runner’s watch and you’re interested in those running dynamics stats (ground contact time, vertical oscillation, etc.), the 630 will get the job done for sure. And at the right price!
Final Thoughts – Garmin Forerunner 630 vs 935 & 630
Get the 645 if you want the onboard music storage feature and you’re not a triathlete. Get the 935 if you are a triathlete, golfer, or open water swimmer that doesn’t care about (or can live without) Garmin Pay or built-in music storage. Get the FR630 if you want an affordable, beastly running watch and you’re fine with not having a wrist HRM.