Featured in this comparison are three outstanding Garmin smartwatches; the Garmin Forerunner 245 Music vs 645 Music vs Vivoactive 4. Each of these three features onboard music storage and is equally well equipped to track your daily activities. The battery life of these three is also impressive. We compare their specs and features head-to-head to find out the differences.
Note that the Forerunner 245 and 645 come in two models while the Vivoactive 4 comes in two sizes. There is the Forerunner 245 and 245 Music, while you have Forerunner 645 and 645 Music. As the names imply, the music editions allow you to store music on the watch which you can listen to offline. On the other hand, the Vivoactive 4 is available in two sizes; Vivoactive 4 and 4s. The difference between the two is that Vivoactive 4 is bigger and has a longer battery life than 4s.
Garmin Forerunner 245 Music vs 645 Music vs Vivoactive 4: Specifications Compared
| Product Info |
 Garmin Forerunner 245 Music Specifications, Features and Price |
 Garmin Forerunner 645 Music Specifications, Features and Price |
 Garmin Vivoactive 4 Specifications, Features and Price |
|---|---|---|---|
| Price | $274.00 | - | $303.00 |
| ABOUT DEVICE | ABOUT DEVICE | ABOUT DEVICE | ABOUT DEVICE |
| Device name | Garmin Forerunner 245 Music | Garmin Forerunner 645 Music | Garmin Vivoactive 4 |
| Device type | Fitness/Sport smartwatch | Fitness/Sport smartwatch | Fitness/Sport smartwatch |
| Gender | Unisex | Unisex | Unisex |
| Release date | April, 2019 | November, 2017 | September, 2019 |
| Predecessor | Garmin Forerunner 235 | — | Garmin Vivoactive 3 |
| Successor | Garmin Forerunner 255 | — | Garmin Vivoactive 5 |
| Versions | Garmin Forerunner 245, Garmin Forerunner 245 Music | Garmin Forerunner 645, Garmin Forerunner 645 Music | Captain Marvel, First Avengers, Vivoactive 4, Vivoactive 4S |
| BODY | BODY | BODY | BODY |
| Dimension | 42.3 x 42.3 x 12.2 mm | 42.5 x 42.5 x 13.5 mm | 45.1 x 45.1 x 12.8 mm |
| Weight | 38.5 grams | 42.2 grams | 50.5 grams |
| Shape | Circular | Circular | Circular |
| Case material | Fiber-reinforced polymer | Fiber-reinforced polymer | Fiber-reinforced polymer |
| Strap material | Silicone | Silicone | Silicone |
| Bezel material | Fiber-reinforced polymer | Stainless steel | Stainless steel |
| Strap size | 20 mm | 20 mm | 22 mm |
| Interchangeable strap | 20mm, Yes | 20mm, Yes | 22 mm, Yes |
| Screen protection | Corning Gorilla Glass 3 | Corning Gorilla Glass 3 | Corning Gorilla Glass 3 |
| Water resistance | Yes, 5ATM | Yes, 5ATM | Yes, 5ATM |
| Durability test | — | — | — |
| Swim-proof | Yes, recommended | Yes, recommended | Yes, recommended |
| Color | Aqua, Black, White | Black, Rose-gold | Black, Silver |
| DISPLAY | DISPLAY | DISPLAY | DISPLAY |
| Display size | 1.2 inches | 1.2 inches | 1.3 inches |
| Display type | LCD, Memory-in-pixel (MIP), transflective | LCD, Memory-in-pixel (MIP), transflective | LCD, Memory-in-pixel (MIP), transflective |
| Display resolution | 240 x 240 px | 240 x 240 px | 260 x 260 px |
| Pixel density | 282.8 PPI | 282.8 PPI | — |
| Always on | Yes | Yes | Yes |
| Custom watch face | Yes | Yes | Yes |
| Input type | (not touchscreen), 5 Physical buttons | (not touchscreen), 5 Physical buttons | 2 Physical buttons, Touchscreen |
| CONNECTIVITY | CONNECTIVITY | CONNECTIVITY | CONNECTIVITY |
| Bluetooth | ANT+, Bluetooth | ANT+, Bluetooth | ANT+, Bluetooth v4.0 |
| Bluetooth calling | No | No | No |
| GPS | Galileo, GLONASS, GPS | Galileo, GLONASS, GPS | Galileo, GLONASS, GPS |
| NFC | No | Yes | Yes |
| Wi-Fi | Yes | Yes | Yes |
| MEMORY | MEMORY | MEMORY | MEMORY |
| RAM | — | — | — |
| ROM | 4GB | 4GB | 4GB |
| Memory card slot | No | No | No |
| CELLULAR CONNECTIVITY | CELLULAR CONNECTIVITY | CELLULAR CONNECTIVITY | CELLULAR CONNECTIVITY |
| Technology | None | None | None |
| SIM type | None | None | None |
| Band | — | — | — |
| NOTIFICATIONS | NOTIFICATIONS | NOTIFICATIONS | NOTIFICATIONS |
| SMS alert | Yes | Yes | Yes |
| Calls alert | Yes | Yes | Yes |
| Email alert | Yes | Yes | Yes |
| Event reminder | Yes | Yes | Yes |
| Third-party apps alert | Yes | Yes | Yes |
| Reply to Notifications | - | - | - |
| MEDIA | MEDIA | MEDIA | MEDIA |
| Audio | mp3/mp4 | mp3/mp4 | mp3/mp4 |
| Bluetooth music | Yes | Yes | Yes |
| Loudspeaker | No | No | No |
| Microphone | No | No | No |
| Camera | No | No | No |
| Radio | No | No | No |
| SENSORS | SENSORS | SENSORS | SENSORS |
| Sensor(s) | — | — | — |
| ACTIVITY TRACKING | ACTIVITY TRACKING | ACTIVITY TRACKING | ACTIVITY TRACKING |
| Blood oxygen | Yes | No | Yes |
| Blood Pressure | No | No | No |
| Calories | Yes | Yes | Yes |
| Distance | Yes | Yes | Yes |
| ECG tracking | No | No | No |
| Heart rate monitoring | Yes | Yes | Yes |
| Sleep tracking | Yes | Yes | Yes |
| Steps | Yes | Yes | Yes |
| Floors climbed | No | Yes | Yes |
| Stress | Yes | Yes | Yes |
| Fall detection | Yes | Yes | Yes |
| Menstrual cycle | Yes | Yes | Yes |
| VO2 Max | Yes | Yes | Yes |
| Swim-tracking | Yes | Yes | Yes |
| Underwater heart rate tracking | Yes | No | Yes |
| On-screen workout | No | No | Yes |
| Sport modes | Yes | Yes | 20 |
| BATTERY | BATTERY | BATTERY | BATTERY |
| Battery type | non-removable Lithium-polymer | non-removable Lithium-polymer | non-removable Lithium-polymer |
| Battery capacity | — | — | — |
| Battery life | GPS mode: 24hrs, Smartwatch mode: 7 days | GPS with music: 5hrs, Smartwatch mode: 7 days | GPS with music: up to 6hrs, Smartwatch mode: up to 8 days |
| Charging type | Charging dock | Charging dock | Charging dock |
| Charging time | 1-2 hours | 1-2 hours | 1-2 hours |
| Solar charging | No | No | No |
| PLATFORM | PLATFORM | PLATFORM | PLATFORM |
| Chipset | — | — | — |
| CPU | — | — | — |
| GPU | — | — | — |
| Operating system | Proprietary OS | Proprietary OS | Proprietary OS |
| MISC | MISC | MISC | MISC |
| Companion app | Garmin Connect | Garmin Connect | Garmin Connect |
| Compatibility | Android, iOS | Android, iOS | Android 5.0+, iOS 11.0+ |
| Payment system | None | Garmin Pay | Garmin Pay |
| Voice command | No | No | No |
| Find my phone | Yes | Yes | Yes |
| Box content | Charger, Garmin Forerunner 245 Music, Manual, Straps | Charger, Garmin Forerunner 645 Music, Manual, Straps | Charger, Garmin Vivoactive 4, Manual, Straps |
Garmin Forerunner 245 Music vs 645 Music vs Vivoactive 4: Fitness Tracking Features
| Garmin Forerunner 245 | Garmin Forerunner 645 | Garmin Vivoactive 4 | |
| Activity Tracking Features Steps counter, floors climbed, fitness age, Move IQ intensity minutes and distanced traveled. | Yes | Yes | Yes |
| Body Battery Energy Monitor Lets you see your body’s energy levels throughout the day so you can find the best times for activity and rest. | Yes | No | Yes |
| Pulse OX Sensor The Pulse Ox sensor gauges your blood oxygen saturation during the day and as you sleep to show how well your body is absorbing oxygen. | Yes | No | Yes |
| Stress Tracking Helps you find out if you’re having a calm, balanced or stressful day. Relax reminders will even prompt you to do a short breathing activity when you’re feeling stressed. | Yes | Yes | Yes |
| Menstrual Cycle Tracking Lets you use the Garmin Connect™ app to track your cycle, log physical and emotional symptoms and learn about training and nutrition during each phase of your cycle. Even get cycle tracking information on your wrist. | No | No | Yes |
| Hydration Tracking Log your daily fluid intake as a reminder to stay hydrated. You can even have an auto goal for hydration that adjusts based on how much sweat you lose during activities — even underwater. | No | No | Yes |
| Respiration Tracking See how you’re breathing throughout the day, during sleep and during breath-work and yoga activities. | No | No | Yes |
| Advanced Sleep Monitoring Get a full picture of how you’re sleeping, with a breakdown of your light, deep and REM sleep stages as well as Pulse Ox and respiration data | Yes | Yes | Yes |
| Heart Rate Tracking The watch constantly samples your heart rate2 and will alert you if it stays high while you’re at rest. It also helps gauge how hard you work during activities even underwater. | Yes | Yes | Yes |
| Mindful Breathing When you want to relax or focus, you can start a breath-work activity, and this watch will track your stress and respiration to help you get a better understanding of how you’re breathing. | No | No | Yes |
| On-Screen Animated Workout Modes Easy-to-follow, animated cardio, strength, yoga and Pilates workouts come preloaded on the watch, and you can download more from the Garmin Connect app. | No | No | Yes |
| Preloaded Workout Modes Track all the ways you move with more than 20 preloaded GPS and indoor sports apps — including walking, running, cycling, pool swimming, golf and more. | Yes | Yes | Yes |
| Garmin Coach Get a personal running coach on your wrist, for free, to help you train for your next 5K, 10K or half-marathon. | Yes | Yes | Yes |
| Safety and Tracking Features When your watch and phone are paired, your live location can be sent to your contacts manually or — during outdoor activities — automatically with built-in incident detection. Also Livetrack, Group LiveTrack and Live event sharing allow you to invite other to join you in your training. | Yes | Yes, lacks Group LiveTrack, Assistance and Live event sharing | Yes, lacks Group Livetrack, Live event sharing |
| Gym & Fitness Equipment Available gym profiles; Strength, Cardio and Elliptical Training, Stair Stepping, Floor Climbing, Indoor Rowing, Pilates and Yoga. | Yes | Fewer | More |
| Training, Planning and Analysis Features Available run profiles; Running, Treadmill Running, Indoor Track Running, Trail Running. GPS speed and distance, customizable activity profiles, advanced training, VO2 Max., heat and altitude acclimation, training load, training effect, auto and manual mutisport activities, Garmin and Strava live segments. | Fewer | Fewer | Fewer |
| ClimbPro Feature Use ClimbPro ascent planner on downloaded courses to see real-time information on your current and upcoming climbs, including gradient, distance and elevation gain. | No | No | No |
| Outdoor Recreation Features Outdoor recreational features include hiking, climbing, mountain biking, skiing, snowboarding, XC skiing, stand up paddleboarding, rowing, kayaking, jumpmaster, tactical | Fewer | Fewer | Fewer |
| Multi-GNSS Support Access multiple global navigation satellite systems (GPS, GLONASS and Galileo) to track in more challenging environments than GPS alone. | Yes | Yes | Yes |
| TOPO Maps Preloaded Topographical (TOPO) maps allow you use TOPO maps with Trendline Popularity Routing to find the best routes and navigate your adventures effortlessly | No | No | No |
| Ski Maps Preloaded Ski maps allow you view run names and difficulty ratings for 2,000 worldwide ski resorts. | No | No | No |
| Round-trip Routing Enter a distance you want to travel, and get suggested routes that will bring you back to your starting point. Trendline™ popularity routing helps you find the best local paths. | No | No | No |
| Turn-by-turn Navigation Follow a route or course with help from turn-by-turn directions, which let you know ahead of time when the next turn is coming. | Yes | Yes | No |
| ABC sensors Navigate your next trail with ABC sensors, including an altimeter for elevation data, barometer to monitor weather and three-axis electronic compass | No | Yes | Yes |
| Running Features Available run profiles include running, treadmill running, indoor track running, trail running | Fewer | Fewer | Fewer |
| PACEPRO Technology A first-of-its-kind PacePro feature helps keep you on pace with grade-adjusted guidance as you run a course. | No | No | No |
| Golf Courses Access full-color CourseView maps for more than 41,000 golf courses around the world, and get button targeting and the PlaysLike Distance feature. | No | No | Yes |
| Swimming Features Available swimming profiles; pool swimming, open water swimming, swimming/running. Other features include; tracks metrics such as distance, pace, stroke count, stroke distance and SWOLF. | Fewer | Fewer | More |
| Underwater Wrist-based Heart Rate Tracking Features underwater wrist-based heart rate tracking that helps you manage your swimming intensity. | Yes | No | Yes |
| Altimeter Floors climbed | No | Yes | Yes |
Garmin Forerunner 245 Music vs 645 Music vs Vivoactive 4: Battery Life
| Forerunner 245 Music | Forerunner 645 Music | Vivoactive 4 |
|
Smartwatch Mode: Up to 7 days GPS mode with music: Up to 6 hours GPS mode without music: Up to 24 hours | Smartwatch Mode: Up to 7 days GPS mode with music: Up to 5 hours GPS mode without music: Up to 14 hours | Smartwatch mode: Up to 5 days GPS mode with music: Up to 6 hours GPS mode without music: Up to 20 hours |
Which is Better?
Each of these three has an inbuilt GPS that enables tracking for outdoor events like routes and locations. Moreover, these three will track your heart rate, calories, stress, steps, and many more advanced fitness metrics.
Although these three share a lot of features in common, there are slight differences in the designs, activity tracking features, and battery life which are stated as follows.
- The Forerunner 645 and Vivoactive 4 have a more durable stainless steel bezel unlike the Forerunner 245 which has a fiber-reinforced polymer bezel.
- The Vivoactive 4 features onscreen animated workouts which are not available on Forerunner 645 and 245. The onscreen animated workouts can guide you through some of your favorite workouts.
- The Forerunner 645 and Vivoactive 4 come with an NFC chip that enables Garmin Pay – a non-contactless payment system that lets you make payments with the watch in supported countries.
- The Forerunner 645 and Vivoactive 4 also have an altimeter that enables these two to count floors climbed. The Forerunner 245 can’t count floors.
- Because the Forerunner 245 and Vivoactive 4 are relatively newer watches, they both can track your heart rate underwater which is not possible with Forerunner 645.
- Furthermore, the Vivoactive 4 and Forerunner 245 being relatively newer smartwatches also feature blood oxygen measurement which is not available in the Forerunner 645.
- The Forerunner 245 features PacePro which offers pace guidance to help you stay on track during training. This is not available on Vivoactive 4 and Forerunner 645.
Bottom line, the Vivoactive 4 and Forerunner 645 have better designs than Forerunner 245. The Vivoactive 4 has the most features, while the Forerunner 245 is a cheaper alternative with a decent amount of features.
