Ensuring your dog's Fi Collar fits correctly is essential for comfort and effective functionality.
If you have an existing collar, lay it flat and measure its length in inches. At its correct size, the collar should allow you to fit two fingers between it and your dog's neck.
No collar yet? No problem. Use a cloth tape measure to loosely measure around your dog's neck where the collar would sit. Add 1 to 3 inches to this measurement, depending on your dog's size, to ensure the collar isn't too tight.
The quickest way to find your size is by your dog's weight. Once you have that, check the charts below for the Fi series you're purchasing to confirm the best fit.
Fi Collar Sizing Charts
Choose the chart for the Fi series you own, then match your dog to a size.
Series 3+ and Series 3 Collars
Match your dog's weight to a band size, then confirm the fit with the neck length.
| Collar Size | Dog Weight | Collar Length | Collar Width | Suggested Breeds |
|---|---|---|---|---|
| Extra Small | Under 10 lb | 9.5" to 11" | 3/4" | Dachshund (miniature), Maltese, Pomeranian, Toy Poodle, Yorkshire Terrier, etc. |
| Small | 10 to 19 lb | 10.5" to 13" | 3/4" | Boston Terrier, Cairn Terrier, Cavalier King Charles, Dachshund, French Bulldog, Jack Russell Terrier, Mini Aussie, Pug, etc. |
| Medium | 20 to 39 lb | 12.5" to 16.5" | 1" | Aussie, Beagle, Border Collie, Corgi, English Bulldog, etc. |
| Large | 40 to 94 lb | 15.5" to 22" | 1" | Boxer, Doberman, German Shepherd, Golden Retriever, Labrador Retriever, Pit Bull, Siberian Husky, Standard Poodle, etc. |
| Extra Large | 95 lb and up | 20" to 31" | 1" | Bloodhound, Great Dane, Great Pyrenees, Mastiff, Newfoundland, Rottweiler, etc. |
Series 2 Collar
Match your dog to a size using the neck length and suggested breeds.
| Collar Size | Collar Length | Suggested Breeds |
|---|---|---|
| Small | 11.5" to 13.5" | Cavalier King Charles, Pekingese, Miniature Schnauzer, French Bulldog, Pug, Scottish Terrier |
| Medium | 13" to 16.5" | American Pit Bull Terrier, Basenji, Beagle, Bedlington Terrier, Bichon Frise, Border Collie, Border Terrier, Boston Terrier, Brittany, Bull Terrier, Cairn Terrier, Cavalier King Charles Spaniel, Cocker Spaniel, Corgi, Dachshund, Fox Terrier, Greyhound, Lhasa Apso, Standard Poodle, Pug, Saluki, Shiba Inu, Springer Spaniel, West Highland Terrier |
| Large | 16" to 22.5" | Afghan, Airedale, Alaskan Malamute, American Eskimo, Australian Shepherd, Australian Cattle Dog, Basset Hound, Belgian Malinois, Black and Tan Coonhound, Boxer, American Bulldog, English Bulldog, Chow, Collie, Dalmatian, Doberman, German Shepherd, German Shorthaired Pointer, Golden Retriever, Irish Setter, Irish Wolfhound, Labrador Retriever, Labradoodle, Old English Sheepdog, Portuguese Water Dog, Rhodesian Ridgeback, Standard Schnauzer, Shar Pei, Siberian Husky, Staffordshire Terrier, Vizsla, Weimaraner, Wheaten Terrier |
| Extra Large | 22" to 30.75" | Akita, Bernese Mountain Dog, Bloodhound, Bullmastiff, Cane Corso, Dogo Argentino, English Mastiff, Great Dane, Great Pyrenees, Newfoundland, Rottweiler, St. Bernard |
Frequently Asked Questions
What size collar should I get for my growing puppy?
Consider starting with an Extra Small, Small, or Medium Fi Collar, depending on your puppy's current size. As your dog grows, you can purchase additional bands to accommodate their changing size.
The Fi Band you receive in your collar box is interchangeable, but limited to its series. To add more, you can purchase additional Fi Bands for the series you need through our online shop.
Can a Fi Series Collar be used on pets other than dogs?
Since we have designed and tested Fi Series Collars specifically for dogs, this product isn't optimized for cats, horses, or any other pet other than dogs. We do not recommend using a Fi Series Collar to track your cat or horse, as we don't expect a comfortable fit or optimal performance.
If you have a cat, we recommend our Fi Mini product instead.
How do I know my dog's Fi Collar is fitting correctly?
Once the Fi Collar is fastened, you should be able to slide two fingers under it comfortably. The collar should be snug but not tight, and it shouldn't be able to slip off your dog's head. This will indicate that your collar is fitting both comfortably and securely.
Is my replacement band the correct size?
The Fi Band is measured differently than a fully assembled collar. To confirm the correct sizing:
Shorten the spare Fi Band to its shortest setting. If your band still has a Fi Device attached, follow the steps for removing your Fi Device first.
Lay the collar flat and measure the length without the device. The spare band lengths should be as follows:
Series 3+ and Series 3 Fi Bands:
- Extra Small: 7.75"
- Small: 8.75"
- Medium: 10.75"
- Large: 13.75"
- Extra Large: 18.25"
Note: The buckle for sizes Extra Small to Medium is plastic. The buckle for Large & Extra Large is metal.
Series 2 Fi Bands:
- Small: 9.50"
- Medium: 10.75"
- Large: 13.75"
- Extra Large: 19.75"
Note: The buckle for size Small is plastic, and the buckle for Medium to Extra Large is metal.