Garmin Forerunner 165 Music vs Garmin Forerunner 45S

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Forerunner 165 Music compared with Forerunner 45S

	GarminForerunner 165 Music	GarminForerunner 45S
Overview
Released
Released	February 2024	May 2019
Display
Case sizes
Case sizes	43 mm	39.5 mm
Panel
Panel	OLED	Memory-in-pixel
Always-on display
Always-on display	Yes	Yes
Display detail
Display detail	1.2-inch (30.4 mm diameter) colour AMOLED touchscreen, 390 x 390 pixels; optional always-on display; five physical buttons	1.04-inch colour MIP display, 208 x 208 pixels, with five-button controls.
Screen protection
Screen protection	Chemically strengthened glass	Chemically strengthened glass.
Health and fitness
ECG
ECG	No	No
Blood oxygen
Blood oxygen	Yes	No
Skin temperature
Skin temperature	No	No
Sleep apnoea alerts
Sleep apnoea alerts	No	No
High blood pressure alerts
High blood pressure alerts	No	No
Body composition
Body composition	No	No
Fall detection
Fall detection	No	No
Crash detection
Crash detection	No	No
GPS
GPS	Single-band	Single-band
Water resistance
Water resistance	50 m	50 m
Sensors
Sensors	Garmin Elevate wrist heart rate; Pulse Ox; barometric altimeter; compass; accelerometer; thermometer; ambient light sensor; GPS, GLONASS and Galileo	GPS, GLONASS, Galileo, Garmin Elevate wrist heart rate and accelerometer.
Health features
Health features	Continuous heart rate with high/low alerts; HRV status; Body Battery; stress, respiration and blood oxygen; advanced sleep and sleep score; sleep coach and nap detection; Health Snapshot; hydration and women's health tracking; no ECG app	All-day heart rate, sleep and stress tracking, plus Body Battery energy monitoring.
Fitness features
Fitness features	Daily suggested running workouts and Garmin Coach plans; training effect and recovery time; wrist-based running dynamics and running power; PacePro; VO2 max and race predictions; pool and open-water swimming; running, cycling, strength, HIIT, yoga, Pilates, tennis, pickleball and padel profiles; point-to-point and breadcrumb course navigation, back-to-start and TracBack; no full offline maps or dedicated triathlon mode; no training readiness, load or status (Wareable and Tech Advisor)	Garmin Coach, VO2 max estimate and profiles for running, cycling, treadmill, elliptical, cardio and yoga activities.
Safety features
Safety features	Incident detection during selected activities, assistance and LiveTrack require a paired compatible smartphone and connectivity; live event sharing is Android-only	Incident detection, assistance and LiveTrack require a paired phone.
Battery and connections
Battery life (maker's claim)
Battery life (maker's claim)	Up to 11 days	Up to 7 days
In low-power mode
In low-power mode	Up to 20 days	–
Mobile data option
Mobile data option	No	No
Works with
Works with	iPhone and Android	iPhone and Android
Storage
Storage	4 GB	–
Battery life detail
Battery life detail	Smartwatch up to 11 days; battery saver smartwatch up to 20 days; GPS-only up to 19 hours; all-systems GNSS up to 17 hours; GPS-only with music up to 7 hours; all-systems with music up to 6.5 hours; actual life depends on display settings, enabled features and use	Up to seven days in smartwatch mode, 12 hours with GPS or 11 hours with GPS and GLONASS, according to Garmin Taiwan. Garmin US lists up to 13 hours in GPS mode.
Charging
Charging	Garmin proprietary plug charging/data cable; rechargeable built-in battery	Rechargeable battery with Garmin charging cable.
Connectivity
Connectivity	Bluetooth and ANT+ and Wi-Fi; stores music for Bluetooth headphones; Spotify, Deezer and Amazon Music downloads require compatible subscriptions; Garmin Pay; Connect IQ apps, watch faces and data fields; smart notifications; Android-only text responses and notification images; Garmin Share and Garmin Messenger; no cellular connection or multi-band GNSS	Smart notifications, phone music controls and Connect IQ watch faces. No on-watch music storage.
Storage
Storage	4 GB memory/history; offline music playback	Stores up to 200 hours of activity data.
Design
Weight (lightest version)
Weight (lightest version)	39 g	32 g (better)
Software
Software	Garmin	Garmin
Case materials
Case materials	Fibre-reinforced polymer bezel; chemically strengthened glass; silicone band; 5 ATM water rating	Silicone band and 5 ATM water rating.
Size
Size	43 x 43 x 11.6 mm; Garmin lists 39 g without a separate body-only weight	39.5 x 39.5 x 11.4 mm; 32 g.
Bands
Bands	20 mm quick-release silicone bands; fits 126–203 mm wrists	Fits wrists 124–185 mm.
Colours
Colours	Black/Slate Grey; Mist Grey/Whitestone; Turquoise/Aqua; Berry/Lilac (currently not sellable on the UK maker page)	White case and band with black display bezel.
In the box
In the box	Forerunner 165 Music; charging/data cable; documentation	–