Compare Fi devices
Fi Mini
The world's smallest, lightest wearable for dogs.
The same AI-powered tracking as Series 3+, in a smaller build for puppies and small dogs.
Fi Series 3+
The most durable, longest lasting dog wearable, ever.
AI-powered GPS and health tracking for medium and large dogs.
Fi Ultra
The world's first satellite-connected dog tracker.
Rugged, long-range tracking for adventure dogs — with T-Satellite powered by Starlink.
Top reasons to buy:
Best for small dogs & puppies
Works with your existing gear
Same GPS & AI monitoring as Series 3+
Top reasons to buy:
Best for med/large dogs
Fully-integrated design
Up to 3-months battery life
Top reasons to buy:
Satellite-connected remote GPS tracking
Works with your existing gear
Fi Callback™ sound/vibration signalling
Tracking & safety
Live location & Lost Dog Mode
Yes
Live location & Lost Dog Mode
Yes
Live location & Lost Dog Mode
Yes
24/7 escape alerts
Yes
24/7 escape alerts
Yes
24/7 escape alerts
Yes
Walk & outdoor history
Unlimited
Walk & outdoor history
Unlimited
Walk & outdoor history
Unlimited
Unlimited users
Yes
Unlimited users
Yes
Unlimited users
Yes
Activity & health
Activity tracking
Yes
Activity tracking
Yes
Activity tracking
No
Sleep tracking
Yes
Sleep tracking
Yes
Sleep tracking
No
AI behavior detection
Yes
AI behavior detection
Yes
AI behavior detection
No
Fi Intelligence
Yes
Fi Intelligence
Yes
Fi Intelligence
No
Health Reports for Vets
Yes
Health Reports for Vets
Yes
Health Reports for Vets
No
AI document organizer
Yes
AI document organizer
Yes
AI document organizer
No
Apple Watch integration
Yes
Apple Watch integration
Yes
Apple Watch integration
Yes
Device & battery
Battery life
Up to 2 monthsUp to 3 months with Fi Base
Battery life
Up to 3 months
Battery life
Up to 5 daysin live tracking
Attaches via
Collar, harness & more
Attaches via
Replaces dog collar
Attaches via
Collar or harness
Weight
16 g
Weight
52 g
Weight
68 g
Dimensions
42 × 30 × 12.5 mm
Dimensions
81.5 × 30.3 × 11.5 mm
Dimensions
75 × 40 × 25 mm
Charging
USB-C
Charging
Fi Base
Charging
USB-C
Waterproof rating
IP68
Waterproof rating
IP68 / 66K
Waterproof rating
IP68 / 66K
Cellular coverage
Verizoncellular coverage
Cellular coverage
AT&Tcellular coverage
Cellular coverage
AT&T + T-MobileLTE-M nationwide
Night light
No
Night light
Yes
Night light
No
Adventure & off-grid
Satellite connection
No
Satellite connection
No
Satellite connection
Yes
Fi Callback™ (Sound & Vibration)
No
Fi Callback™ (Sound & Vibration)
No
Fi Callback™ (Sound & Vibration)
Yes
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