Garmin Forerunner 645 vs 935 vs 945 Compared

Featured in this comparison are three fitness-focused GPS smartwatches for serious fitness enthusiasts; the Garmin Forerunner 645 vs 935 vs 945 – which is the best? While the Forerunner 945 is a premium and more equipped smartwatch featuring more features, the Forerunner 645 and 935 are nice cheaper alternatives.

Note that the Forerunner 645 comes in two editions; Forerunner 645 and 645 Music. The Music edition allows you to load music onboard the watch which you can listen to offline via a Bluetooth headset. It also features incidental fall detection not present in the non-music edition. Featured in this comparison chart is the Forerunner 645 music edition.

Garmin Forerunner 645 vs 935 vs 945: Specifications Compared

Garmin Forerunner 645 vs 935 vs 945: Fitness Tracking Features

	Garmin Forerunner 645	Garmin Forerunner 935	Garmin Forerunner 945
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.	No	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.	No	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	Yes	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	No
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	No
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, lacks Group LiveTrack, Assistance and Live event sharing	Yes, lacks Assistance, Live event sharing, and incidental fall detection	Yes
Gym & Fitness Equipment Available gym profiles; Strength, Cardio and Elliptical Training, Stair Stepping, Floor Climbing, Indoor Rowing, Pilates and Yoga.	Fewer	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	More
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	Yes
Outdoor Recreation Features Outdoor recreational features include hiking, climbing, mountain biking, skiing, snowboarding, XC skiing, stand up paddleboarding, rowing, kayaking, jumpmaster, tactical	Fewer	Fewer	More
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	Yes
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	Yes
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	Yes
ABC sensors Navigate your next trail with ABC sensors, including an altimeter for elevation data, barometer to monitor weather and three-axis electronic compass	Yes	Yes	Yes
Running Features Available run profiles include running, treadmill running, indoor track running, trail running	Fewer	Fewer	More
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	Yes
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	Yes	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.	No	No	Yes
Altimeter Floors climbed	Yes	Yes	Yes

Garmin Forerunner 645 vs 935 vs 945: Battery Life

Forerunner 645	Forerunner 935	Forerunner 945
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 2 weeks GPS/HR mode: Up to 24 hours UltraTrac™ mode: Up to 60 hours without wrist heart rate	Smartwatch Mode: Up to 2 weeks GPS mode with music: Up to 10 hours GPS mode without music: Up to 36 hours

Which is Better?

Although these three have a lot of features in common, there are slight differences which are stated below;

• While the Forerunner 645 has a stainless steel bezel, the Forerunner 945 and 935 have bezels made of fiber-reinforced polymer.
• The glass types also differ, while the Forerunner 935 has a chemically strengthened glass, the 645 has a Corning Gorilla Glass 3, while the 945 has a more advanced Corning Gorilla Glass DX.
• The Forerunner 645 music is equipped with about 4GB capacity that allows you to load music into the watch. The Forerunner 945 comes with twice bigger 8GB storage that lets you load even more of your favorite tracks from popular music services. Meanwhile, the 935 lacks onboard music support.
• When your phone is nearby, the Forerunner 645 and 945 can detect a hard fall and will automatically start a call on your phone. This isn’t possible with Forerunner 935.
• Forerunner 945 features Pacepro that offers pace guidance to help you stay on track during training. This is not available on Forerunner 645 and 935.
• The Forerunner 645 and 945 are both equipped with an NFC chip that enables Garmin Pay which will allow you to make payments from the watch.
• The Forerunner 945 features preloaded TOPO and road/trail maps with Trendline Popularity Routing. It also features a routable cycling-specific street map.
• The Forerunner 945 is also preloaded with 42000 golf courses as well as equipped with more golfing tools.
• The Forerunner 935 and 945 can track both indoor and open water metrics such as distance, pace, stroke count/rate, stroke distance, swim efficiency (SWOLF), and calories, while the 645 can only track indoor swimming metrics.
• The Forerunner 945 can track your heart rate underwater. The 935 and 645 lack underwater heart rate tracking.
• The Forerunner 935 and 945 have about two weeks of battery life, this is twice of about 7 days with the Forerunner 645.

Bottom line, the Forerunner 945 is a far more equipped smartwatch than its predecessor and the Forerunner 645. It features maps, higher music storage, and more activity tracking features.

On the flip side, the Forerunner 645 Music and 935 are cheaper alternatives.

Garmin Forerunner 945 vs Fenix 5X Plus

Featured in this comparison chart are two of Garmin’s finest multisport GPS smartwatches; the Garmin Forerunner 945 and Fenix 5X Plus. While the Forerunner 945 succeeds 935, the Fenix 5X Plus is succeeded by the Fenix 6X Pro which is one of the members in the Fenix 6 Series. Each of these two is an outstanding smartwatch; durable, loaded with lots of activity tracking features, and equipped with long battery life. Compare these two fantastic GPS smartwatches to find out the differences.

Garmin Forerunner 935 vs 945 vs Fenix 5X Plus: Specifications Compared

Garmin Forerunner 945 vs Fenix 5X Plus: Fitness Tracking Features

	Garmin Forerunner 945	Garmin Fenix 5x Plus
Activity Tracking Features Steps counter, floors climbed, fitness age, Move IQ intensity minutes and distanced traveled.	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
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	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
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.	Yes	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.	Yes	No
Respiration Tracking See how you’re breathing throughout the day, during sleep and during breath-work and yoga activities.	Yes	No
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
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
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
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
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
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
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 Live event sharing
Gym & Fitness Equipment Available gym profiles; Strength, Cardio and Elliptical Training, Stair Stepping, Floor Climbing, Indoor Rowing, Pilates and Yoga.	More	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.	More	More
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.	Yes	Yes
Outdoor Recreation Features Outdoor recreational features include hiking, climbing, mountain biking, skiing, snowboarding, XC skiing, stand up paddleboarding, rowing, kayaking, jumpmaster, tactical	More	More
Multi-GNSS Support Access multiple global navigation satellite systems (GPS, GLONASS and Galileo) to track in more challenging environments than GPS alone.	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	Yes	Yes
Ski Maps Preloaded Ski maps allow you view run names and difficulty ratings for 2,000 worldwide ski resorts.	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.	Yes	Yes
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
ABC sensors Navigate your next trail with ABC sensors, including an altimeter for elevation data, barometer to monitor weather and three-axis electronic compass	Yes	Yes
Running Features Available run profiles include running, treadmill running, indoor track running, trail running	More	More
PACEPRO Technology A first-of-its-kind PacePro feature helps keep you on pace with grade-adjusted guidance as you run a course.	Yes	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.	Yes	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.	More	More
Underwater Wrist-based Heart Rate Tracking Features underwater wrist-based heart rate tracking that helps you manage your swimming intensity.	Yes	No
Altimeter Floors climbed	Yes	Yes

Garmin Forerunner 945 vs Fenix 5X Plus: Battery Life

Forerunner 945	Fenix 5X Plus
Smartwatch Mode: Up to 2 weeks GPS mode with music: Up to 10 hours GPS mode without music: Up to 36 hours	Smartwatch: Up to 20 days GPS: Up to 32 hours GPS and Music: Up to 13 hours UltraTrac™ mode: Up to 70 hours