Garmin · 2019
Forerunner® 45SSize, Dimensions & Wrist Fit
The Garmin Forerunner® 45S sits best on flat wrist widths of about 42–56mm (≈ 11.2–15.0cm wrist circumference). Adjust the slider below to check your wrist.
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The Forerunner® 45S in short
The figures that decide whether this watch suits you, pulled out of the full specification sheet further down.
- Rated for 7 days of use per charge.
- Water rated to 5 ATM.
- 32g on the wrist. Lighter than 83% of the 40mm watches we have weights for.
- 1.04" (26.3 mm) diameter Sunlight-visible, transflective memory-in-pixel (MIP) display.
- chemically strengthened glass case, chemically strengthened glass glass.
Does the Forerunner® 45S fit your wrist?
Drag the slider to your wrist width and see the Forerunner® 45S overlaid at true scale. Lug-to-lug — not case diameter — decides whether a watch overhangs your wrist.
Happy with the fit? Check current availability for the Forerunner® 45S.
Check offer2D Dimension Schematics
The Forerunner® 45S drawn to scale — from above, and in profile against the wrist.
- Garmin Forerunner® 45S39.5mm · 11.4mm thick
3D preview
Garmin Forerunner® 45S on a wrist
On an arm sized to your own wrist — the view a product photo never gives you.
Shapes are built from published measurements, not manufacturer 3D models — accurate proportions, generic dial.
Forerunner® 45S battery life
The runtime the manufacturer publishes for everyday use.
- Smartwatch7 days
How the Forerunner® 45S ranks on battery
Against the 268 Garmin watches in our database, ranked on each figure Garmin publishes.
- Everyday use7 days#208 of 257
Forerunner® 45S specifications
The figures that decide a purchase, followed by every line Garmin publishes.
- Battery life
- Smartwatch Mode: Up to 7 days GPS mode: Up to 13 hours
- Display
- 1.04" (26.3 mm) diameter
- Resolution
- 208 x 208 pixels
- Water rating
- 5 ATM
- Glass
- chemically strengthened glass
- Strap
- silicone
- Storage
- 80 hours of activity data
- Charging
- Garmin proprietary plug charger
Full specification sheet
86 published lines across 14 groups, unedited
Overview
- Family
- Garmin
General
- Battery life
- Smartwatch Mode: Up to 7 days GPS mode: Up to 13 hours
- Display Size
- 1.04" (26.3 mm) diameter
- Color display
- Lens Material
- chemically strengthened glass
- Memory/History
- 80 hours of activity data
- Strap material
- silicone
- Charging method
- Garmin proprietary plug charger
- Display resolution
- 208 x 208 pixels
Sensors
- GPS
- GLONASS
- Galileo
- Accelerometer
- Garmin Elevate™ wrist heart rate monitor
Product Info
- Main SKU
- 010-02156-00
- Product ID
- 682416
- Product Name
- Forerunner® 45S
- Release Date
- 4/30/2019
- Product Variation
- White
Clock Features
- Timer
- Stopwatch
- Time/date
- Alarm clock
- GPS Time Sync
- Automatic daylight saving time
Cycling Features
- Speed and cadence sensor support (w/sensor)
- Alerts (triggers alarm when you reach goals including time, distance, heart rate or calories)
Running Features
- Run workouts
- Foot pod capable
- GPS-based distance, time and pace
- Cadence (provides real-time number of steps per minute)
What You'll Love
- Display type
- Sunlight-visible, transflective memory-in-pixel (MIP)
- Water rating
- 5 ATM
- Battery life (smartwatch mode)
- Up to 7 days
Activity Profiles
- Gym
- Cardio, Elliptical Training, Stair Stepping
- Cycling
- Biking, Indoor Biking
- Wellness
- Yoga
- Indoor running
- Treadmill Running, Indoor Track Running
- Outdoor running
- Running
Daily Smart Features
- Calendar
- Connectivity
- Find My Phone
- Find My Watch
- Weather forecasts
- Smart Notifications
- Smartphone compatibility
- iPhone®, Android™
- Controls smartphone music
- Pairs with Garmin Connect™ Mobile
- Connect IQ™ (downloadable watch faces, data fields and apps)
- yes (watch faces only)
Activity Tracking Features
- TrueUp™
- Move IQ™
- Step counter
- Calories burned
- Distance traveled
- Intensity minutes
- Move alerts (displays on device after a period of inactivity)
- Auto goal (learns your activity level and assigns a daily step goal)
Health & Wellness Monitoring
- Sleep
- yes (advanced)
- Fitness age
- yes (in app)
- All-day stress
- Resting heart rate
- Abnormal heart rate alerts
- yes (high and low)
- Relaxation breathing timer
- Body Battery™ energy monitor
- Wrist-based heart rate (constant, every second)
Safety and Tracking Features
- Assistance
- yes (smartphone required)
- Live Event Sharing
- Android™ Only
- Incident Detection during select activities
- yes (smartphone required)
Training, Planning and Analysis Features
- HR zones
- HR alerts
- Manual lap
- HR calories
- Voice alerts
- Physio TrueUp
- VO2 Max (Run)
- Advanced workouts
- Interval training
- GPS speed and distance
- Customizable data pages
- Touch and/or button lock
- Activity history on watch
- Downloadable training plans
- Customizable activity profiles
- Auto Pause® automatic timer halt
- Auto Lap® interval tracking feature
- HR broadcast (broadcasts HR data over ANT+® to paired devices)
Alternatives to the Forerunner® 45S
Watches that cover a similar amount of wrist, with the measurements that separate them.
Garmin
Instinct® E – 40 mm
- Width
- 40mm
- Thick
- 13.6mm
- Weight
- 41g
Garmin
Instinct® 2S - Standard Edition
- Width
- 40mm
- Thick
- 13.3mm
- Weight
- 42g
Garmin
Instinct® 2S - Camo Edition
- Width
- 40mm
- Thick
- 13.3mm
- Weight
- 42g
Garmin
Instinct® 2S Solar
- Width
- 40mm
- Thick
- 13.3mm
- Weight
- 43g
Garmin
Vivomove Sport
- Width
- 40mm
- Thick
- 11mm
- Weight
- 33.8g
Garmin
Vivoactive 4S
- Width
- 40mm
- Thick
- 12.7mm
- Weight
- 40g
Forerunner® 45S — Frequently Asked Questions
Will the Garmin Forerunner® 45S fit my wrist?
The Garmin Forerunner® 45S looks balanced on flat wrist widths of roughly 42–56mm (about 11.2–15.0cm circumference). Drag the slider above to check it against your own measurement.
How long does the Garmin Forerunner® 45S battery last?
Garmin rates it at 7 days per charge in everyday use.
How does the Garmin Forerunner® 45S battery compare with other Garmin watches?
At 7 days in everyday use it ranks #208 of the 257 Garmin watches in our database — below the middle of the range. The full ranking, including GPS and power-saving figures, is on our Garmin battery life comparison.
Is the Garmin Forerunner® 45S thick for a 40mm watch?
At 11.4mm, middle of the pack for thickness at this width. Thickness, not case width, is what decides whether a watch catches on a shirt cuff.
What other watches are the same size as the Garmin Forerunner® 45S?
TAG Heuer Aquaracer Professional 200 Solargraph 40 UK Limited Edition, Xiaomi Redmi Watch 6, Vivo Watch GT 2 - Bluetooth, Samsung Galaxy Watch8 - LTE · 40mm all sit within half a millimetre of the Garmin Forerunner® 45S's 39.5mm case, so they cover the same amount of wrist.
