Quick Answer: Buy the Fi Series 3+ (about $189 including a 12-month membership) if your dog is an escape artist, a chewer, or a big strong breed — it’s a rugged, built-in smart collar with fast escape alerts and an up-to-3-month battery (per Fi) thanks to smart WiFi/cellular switching. Buy the Jiobit (about $130) if you have a small dog, a cat, or a mixed pet-and-kid household — it’s one of the smallest cellular trackers made, weighing just 0.6 oz (17 g) (per Life360), and it clips to any collar. Both need a subscription and both deliver similar 10–30 ft accuracy. In short: Fi wins on durability and battery; Jiobit wins on size and versatility.

Fi and Jiobit come at the same problem — “where is my pet right now?” — from opposite directions. Fi is a premium built-in smart collar engineered for dogs that bolt, with a chew-resistant build and a battery measured in months. Jiobit is a tiny clip-on tracker from Life360 that disappears onto any collar and works just as well on a cat, a puppy, or even a kid. We put the current Fi Series 3+ and the Jiobit head-to-head on the five things that actually matter — battery, size, accuracy, escape features, and subscription cost — so you can pick the right one the first time.

Fi vs Jiobit by the numbers

Fi vs Jiobit at a glance

SpecFi Series 3+Jiobit (Life360)
Best forEscape artists & batterySmall pets & versatility
Hardware price~$189 (incl. 12-mo membership)~$130
Battery lifeUp to ~3 months (per Fi)~5–7 days live / ~30 days power-save
SubscriptionFrom ~$99/6-mo (prepaid)From ~$8.33/mo
WeightFull collar0.6 oz (17 g)
DesignBuilt-in smart collar (dogs)Clip-on (any collar, any pet or kid)
NetworkAT&T LTE-M (U.S.)GPS + 4G LTE + BT + WiFi
Live rangeUnlimitedUnlimited
Accuracy (open area)~10–30 ft~10–30 ft
Water resistanceWaterproofWater resistant
Rating★★★★½ (rugged)★★★★½ (compact)

Fi Series 3+ — Best for escape artists and battery

Fi Series 3+ Smart Dog Collar

Best durability & battery · ~$189 incl. 12-mo membership (+ ~$20 activation)
  • Up to ~3 months of battery for mostly-home dogs, per Fi — the longest in the category — via smart WiFi/cellular switching.
  • Rugged, chew-resistant built-in collar designed for dogs that bolt or dig.
  • Custom virtual fences with instant escape alerts, then live updates every few seconds if your dog gets out.
  • Step counting and activity tracking with daily goals and breed comparisons.
  • Waterproof, with an LED for night walks and Apple Watch compatibility.
  • Trade-off: full-size collar (not for cats/toy breeds), higher upfront cost, and a U.S.-only AT&T LTE-M network.
Check price on Amazon →

Fi is built for the dog that doesn’t stay put. The Series 3+ is a built-in smart collar — not a clip-on — made from a rugged, chew-resistant material that survives diggers and escape artists. Its headline feature is endurance: because it uses WiFi when your dog is home and only switches to cellular when they leave a known zone, Fi rates the battery at up to 3 months per charge for mostly-home dogs (expect roughly 3 weeks if GPS refreshes every few minutes). That means it’s actually charged on the day your dog slips the fence.

When a dog does get out, Fi’s custom geofences fire an escape alert the instant they cross the line, then push real-time updates every few seconds as they roam. The price is the obvious downside — about $189 including the first year of membership, plus a one-time ~$20 activation fee, with prepaid renewals from roughly $99/6 months afterward — and the AT&T LTE-M network makes it a U.S.-focused device. For escape artists, big strong breeds, and anyone tired of nightly charging, that premium buys real peace of mind.

Jiobit — Best for small pets and whole-family versatility

Jiobit GPS Tracker (by Life360)

Best size & versatility · ~$130 + subscription from ~$8.33/mo
  • Just 0.6 oz (17 g) and about 1.5 x 1.1 x 0.4 in — one of the smallest cellular GPS trackers made, per Life360.
  • Clips to any collar, and works equally well on a cat, puppy, kid, or elderly relative.
  • GPS plus 4G LTE, Bluetooth, and WiFi; refreshes every 8–10 seconds in Live View.
  • Water resistant and shock-proof, built to survive whatever a pet gets into.
  • Real-time location sharing and geofenced place alerts through the Life360 app.
  • Trade-off: shorter ~5–7 day Live-View battery (up to ~30 days in power-save) and no built-in collar of its own.
Check price on Amazon →

Jiobit’s pitch is the opposite of Fi’s: instead of a rugged, dog-specific collar, it’s a featherweight tag that goes anywhere. At 0.6 oz (17 g) it’s small enough for a cat or a toy breed that a full Fi collar would overwhelm, and because it clips to any collar you already own, one Jiobit can move between pets — or onto a child’s belt loop. That whole-family flexibility, backed by the Life360 ecosystem, is its real selling point.

The catch is battery. In Live View the Jiobit lasts roughly 5–7 days per charge, stretching to about 30 days in power-save mode (per Life360), so it needs recharging more often than a mostly-home Fi. Hardware runs about $130, and subscriptions start near $8.33/month on annual plans (closer to $15/month month-to-month). For owners of small pets, multi-pet households, or families who want a single tracker platform for pets and people, those trade-offs are easy to accept.

Which should you buy?

Neither is a wrong answer — they’re optimized for different pets and different owners. If durability and battery lead your list, Fi wins. If size and cross-pet versatility lead, Jiobit wins.

How these two fit the wider market

Fi and Jiobit aren’t your only options. If price is your top concern, the affordable clip-on Tractive GPS undercuts both on hardware and monthly cost, and our Tractive vs Fi breakdown pits it directly against the Fi collar. If you want the deepest look at Fi’s full lineup, see our Fi smart collar review; for Jiobit on its own, read our Jiobit tracker review. Tracking the smallest pets? Start with the smallest GPS dog trackers or the best GPS cat tracker. And if monthly fees are a dealbreaker, both of these require a plan — read our guide to a GPS dog tracker with no subscription first. For the full field, begin with our best GPS dog tracker roundup.

The bottom line

The Fi vs Jiobit decision comes down to one question: is your priority a rugged dog-specific collar with the longest battery, or a tiny, versatile tracker that fits any pet? Fi delivers an up-to-3-month battery, a chew-resistant built-in collar, and instant geofence escape alerts — the smart pick for escape artists and big breeds. Jiobit answers back at just 0.6 oz, clipping onto any collar (or a kid), for owners of small pets and mixed households. Match the tracker to your pet, and either one will do the core job — knowing where they are — reliably.