Fi Series 3 Dog Collar Review

Quick Answer

The Fi Series 3 Dog Collar takes the crown here as the best GPS tracker and activity monitor for dogs. Its sturdy build, solid battery life, and smart tracking features give you real peace of mind, whether you’re hiking or just want to know your escape artist hasn’t broken out again.

Our Top Picks

Product	Best For	Key Spec	Price Tier
Fi Series 3 Dog Collar	Versatile tracking	GPS, 3-5 days battery life	Mid-range
Whistle Go Explore	Health monitoring	GPS, health tracking	Mid-range
Garmin Alpha 200i	Hunting dogs	GPS, 80 hours battery life	Premium
Tractive GPS Tracker	Real-time tracking	GPS, unlimited range	Budget
Petfon Pet GPS Tracker	Small dogs	GPS, up to 16 hours battery life	Mid-range

Detailed Reviews

1. Fi Series 3 Dog Collar

Overview

The Fi Series 3 is my top pick for a reason. This GPS and activity tracker hits that sweet spot between durability and smart features. Your adventure-loving pup can’t break it, and you’ll actually use all its features.

Key Specs

• Battery Life: 3-5 days with regular GPS use; Fi advertises up to three months in activity-tracking mode
• Water Resistance: IP68 and IP66K, per Fi’s Series 3 launch post
• Build: Stainless steel frame rated to withstand over 400 lbs of pull force
• GPS Tracking: Real-time over LTE-M
• Activity Tracking: Yes

Pros

• Long battery life
• Accurate GPS tracking
• Durable and waterproof

Cons

• Pricier than basic trackers
• Monthly subscription needed for full features

Best For

Dog owners who want reliable tracking plus health monitoring without the complexity of pro-level gear.

2. Whistle Go Explore — discontinued

Overview

Tractive acquired Whistle from Mars Petcare in July 2025 and the trackers were subsequently switched off, so treat this entry as historical — the full account is in our Tractive vs Whistle explainer. While it ran, it tracked more health data than anything else in the category, and the GPS was almost secondary. We put the two side by side in our Whistle GO Explore versus Fi Series 3 comparison if you’re torn between them.

Key Specs

• Battery Life: 20 days
• Water Resistance: IP68
• GPS Tracking: Yes
• Health Tracking: Yes

Pros

• Impressive 20-day battery life
• Detailed health monitoring
• User-friendly app

Cons

• Bulkier than it needs to be
• Monthly subscription required

Best For

Health-conscious pet parents who want detailed activity and wellness tracking alongside location monitoring.

3. Garmin Alpha 200i

Overview

This is serious gear for serious dog people. Hunters and trainers swear by it, but honestly, most regular dog owners will find it overkill. The 80-hour battery life is ridiculous though.

Key Specs

• Battery Life: 80 hours
• Water Resistance: IPX7
• GPS Tracking: Yes
• Training Features: Yes

Pros

• Crazy long battery life (80 hours!)
• Professional-grade tracking and training tools
• Built like a tank

Cons

• Expensive, premium tier
• Complex setup that might frustrate casual users

Best For

Hunters and professional trainers who need bulletproof gear and don’t mind paying for it.

4. Tractive GPS Tracker

Overview

The budget pick that doesn’t totally suck. It’s lightweight and gets the job done, though you’ll be charging it more often than the pricier options. For the price, I can’t complain much, but it does lose ground on durability once you line it up against the Fi directly.

Key Specs

• Battery Life: 2-5 days; Tractive’s DOG 6 page quotes up to two weeks with Power Saving Zones on
• Water Resistance: IP68
• GPS Tracking: Yes — LIVE mode updates every 2–3 seconds
• Coverage: 175+ countries on 2G and/or LTE CatM1

Pros

• Actually affordable
• No range limits
• Won’t weigh down small dogs

Cons

• Battery dies faster than I’d like
• Still needs a monthly subscription

Best For

Budget-conscious owners or those with small dogs who just need basic GPS tracking.

5. Petfon Pet GPS Tracker

Overview

The no-subscription option sounds great until you realize why it’s cheaper. The 3km range limit and short battery life are deal-breakers unless you live somewhere very rural and never go far.

Key Specs

• Battery Life: Up to 16 hours
• Water Resistance: Not specified
• GPS Tracking: Yes
• Range: Up to 3 km

Pros

• No monthly fees (finally!)
• Compact and light
• Real-time tracking within range

Cons

• Only 3km range (seriously limiting)
• Battery barely lasts a day

Best For

Rural pet owners who stay close to home and hate subscription fees more than they hate limited functionality.

How We Evaluated

We compared these collars on what actually matters:

• Performance: Real-world accuracy and reliability
• Battery Life: How often you’ll curse yourself for forgetting to charge it
• Tracking Features: GPS precision and useful extras like health monitoring
• Value: Bang for your buck, including those sneaky subscription costs
• User Feedback: What other dog owners actually say after living with these things

Buying Guide

Here’s what to think about before buying:

• Purpose: Just GPS tracking, or do you want health data too?
• Size and Fit: A collar that doesn’t fit right is useless and uncomfortable
• Battery Life: Longer battery = less hassle
• Durability: Match the collar to your dog’s destruction level
• Subscription Fees: Factor in the monthly costs – they add up fast

FAQ

1. Is the Fi Series 3 Dog Collar waterproof?

Yes, it’s IP68 rated. Your dog can swim, roll in mud, or get caught in a downpour without you worrying about the collar.

2. Do I need a subscription for the Fi Series 3?

Yeah, you’ll need to pay monthly for the full feature set. Basic GPS works without it, but you’re missing out on the good stuff.

3. Which tracker lasts longest between charges?

Among current models, Tractive’s XL variants go furthest — its DOG 6 page quotes up to two weeks for the standard tracker and up to six weeks for the XL, both with Power Saving Zones enabled. Fi advertises up to three months, but only in activity-tracking mode with GPS mostly asleep.

4. Can I use the Tractive GPS Tracker without a smartphone?

Nope, you need the app to track your dog. But the app is pretty decent, so that’s not really a problem.

5. What size dogs are the Petfon Pet GPS Tracker suitable for?

Small to medium dogs work best. The lightweight design won’t bother smaller pups, but bigger dogs might find the range limiting. If you have a toy breed, start with our roundup of trackers sized for small dogs instead.

Recommendation

Go with the Fi Series 3 Dog Collar for most situations. It balances features, durability, and usability better than anything else we compared. If you’re obsessed with health metrics, Tractive’s Premium tier now carries the heart-rate and respiratory monitoring that used to be Whistle’s calling card. Skip the others unless you have very specific needs or a tight budget. And if all you really want is a cheap way to locate a lost dog, weigh the collar against Apple’s AirTag approach before you spend the money.