Free puppy and dog tool
Find a starting size, then check the fit
By Michael Northcutt, PhD · Last updated
The crate listing says 24, 30, 36, 42 or 48 inches, and your puppy fits in a shoebox. Guess low, and she outgrows it. Guess high with no plan, and the back corner can become her toilet. Tell us her breed, her expected adult weight or her measurements. You get the crate length to buy for the grown dog, and where the divider goes tonight.
Quick answer. Measure her standing, from nose to tail tip and from the top of her head to her feet. Add 3 to 4 inches to each, as the AKC advises. Then buy the smallest crate that clears both numbers.
For a puppy, size it for the dog she’ll grow into. Cornell’s canine health center says a divider can shrink the crate to fit her while she grows.
No tape measure? PetMD’s vet-reviewed chart pairs each crate with a weight range, such as 42 inches for 71 to 90 pounds.
Need help choosing a crate style? Read our puppy crate sizing guide.
Your crate size
Pick her breed, or enter her weight or measurements, then tap “Show my crate size.”
Where the divider goes today
Check the model’s usable interior length and height before buying. Listed crate sizes can describe outside dimensions.
How does the calculator pick a crate size?
It runs every rule that fits what you entered. Then it takes the biggest crate any rule asks for. A roomy crate can be divided. A short one can’t grow.
- Measured to the tail tip. That’s the AKC’s method, with height from head to feet while she stands. It adds 3 to 4 inches to each number. We add 4.
- Measured to the tail base. PetSmart and MidWest measure this way. PetSmart adds 2 to 4 inches, and we add 4 here too.
- Measured sitting. PetMD wants 2 inches or more of space over her head when she sits.
- PetMD’s chart. Each crate has a longest and a tallest dog it fits. We pick the first crate that fits her on both.
- Breed or weight. We check PetMD’s chart and MidWest’s chart. When they split, we take the bigger crate.
PetMD says to go up a size if any fit test is too tight. PetSmart says to size up when she falls between sizes.
| Crate | Longest dog | Tallest dog | Adult weight, PetMD | Adult weight, MidWest |
|---|---|---|---|---|
| 18 in. | 10 in. | 10 in. | Up to 6 lbs | 1 to 6 lbs |
| 22 in. | 16 in. | 12 in. | Up to 12 lbs | 7 to 11 lbs |
| 24 in. | 18 in. | 14 in. | 13 to 25 lbs | 12 to 20 lbs |
| 30 in. | 24 in. | 18 in. | 26 to 40 lbs | 21 to 40 lbs |
| 36 in. | 30 in. | 20 in. | 41 to 70 lbs | 41 to 70 lbs |
| 42 in. | 36 in. | 24 in. | 71 to 90 lbs | 71 to 90 lbs |
| 48 in. | 42 in. | 26 in. | 90 to 110 lbs | 91 to 110 lbs |
Longest dog, tallest dog and PetMD weights come from PetMD’s dog crate sizing chart. MidWest weights come from the MidWest crate sizing guide. MidWest also lists a 54-inch crate for dogs over 110 pounds.
How do you measure a wiggly puppy for a crate?
Shopping for a crate? Click Here To Download The Free Crate Fit Card. Record measurements before choosing a model.
Get her standing on all four paws, with a helper and a pocket of treats. MidWest suggests keeping lots of treats on hand so she holds still. Run the tape from her nose to her tail tip. Then measure from the floor to the top of her head.
Ears that stand up count. PetSmart measures to the top of her head or the tip of her ears, whichever is taller. It also suggests measuring more than once, so take two readings and keep the bigger one.
Her numbers today set the divider. Her adult numbers pick the crate. For a growing puppy, you’ll usually lean on breed or weight for now. Our puppy crate size guide walks through the full measuring method, step by step.
Where should the crate divider go tonight?
Give her room to stand, turn around and lie down comfortably, and no more. The calculator takes her length today, adds 4 inches and gives you that space.
- Panel across the width. Slide it in across the crate’s width and make it snug, as MidWest advises.
- Move it back slowly. MidWest says to check her size regularly and widen the space gradually.
- Missing a divider? Use a compatible divider secured according to the manufacturer’s instructions. Do not improvise with loose pillows or chewable fillers.
If the crate is too large, she can make one side a bed and the other a toilet (Cornell).
Puddles at the back even with the panel snug? She may be holding it longer than she can. Our free Potty Break Timer shows when she needs out next.
Why do breed, weight and her measurements give different sizes?
Charts describe a typical dog, and yours may be longer, lighter or taller. PetMD says to base the crate on her measurements, not her weight or breed alone. Each dog is an individual.
Brand charts split too. MidWest puts a Beagle in a 36-inch crate, while PetMD lists Beagles with the 30-inch. MidWest’s breed chart warns that sex and mixed ancestry may mean a bigger or smaller crate.
So use breed or weight to buy for a puppy, and take the bigger answer. Once she’s grown, enter her real measurements here. If she fails a fit test, go up a size.
Is she grown, house-trained and crated only to prevent destructive behavior? Cornell allows a larger crate with extra room to stretch out.
Crate size questions
Is crate size measured inside or outside?
Check the model’s usable interior measurements. Listed sizes may describe outside dimensions, and wall shapes can reduce usable space.
Does a bed in the crate change the size I need?
It can. PetMD notes that crate mats and dog beds take up space. Plan for the bedding you’ll use when you measure her and when you buy.
Can I buy a small crate now and a bigger one later?
Yes. PetMD calls buying several crates as she grows a good choice when her grown size is hard to guess. With a divider panel, MidWest says one crate can last her whole life.
What size crate does a 50 pound dog need?
Both charts suggest a 36-inch crate for dogs weighing 41 to 70 pounds. Confirm the actual interior dimensions before buying. PetSmart’s Large band for 41 to 70 pounds runs 36 to 42 inches. Check her length too, since PetMD’s 36-inch fits dogs up to 30 inches long.
Crate bought and set up? Our crate training a puppy guide shows how to help her like going in.
About the author
Michael Northcutt, PhD
Founder, LoveMyPuppy.store · Certified Pet Therapy Specialist · Certified Companion Animal Rehabilitation Therapist (CCAT) · Member, AAPT Certification Board
Dr. Michael Northcutt is a pet therapy and companion-animal rehabilitation professional with 14 years of experience. His work covers animal-assisted interventions, rehabilitation, animal welfare and the human-animal bond. He holds the Certified Companion Animal Rehabilitation Therapist (CCAT) credential from North Carolina State University College of Veterinary Medicine. He also serves on the Animal Assisted Play Therapy® (AAPT) Certification Board. He was a keynote speaker at the 2017 International Veterinary Symposium Conference.
His core principle: what we do for an animal should support its health, comfort, safety and quality of life. Not a veterinarian.
Sources
- American Kennel Club. How to Choose the Best Crate for Your Dog: measure standing, nose to tail tip and head to feet, then add 3 to 4 inches to each.
- PetMD. How To Choose the Right Crate Size for Your Dog or Puppy, by Rebecca Bermingham, CVT, reviewed by Jennifer Coates, DVM: the sizing chart, 2 inches of head clearance, going up a size, beds take space, bedding in place of a divider, several crates as she grows.
- MidWest Homes for Pets. What Size Crate Should I Get? and the crate size and breed chart: weight bands, breed sizes, treats while measuring, divider fit and timing.
- PetSmart. Dog Crate Size Chart: Finding the Perfect Fit: tail base and ear tips, add 2 to 4 inches, measure more than once, size up between sizes, inside dimensions.
- Cornell Richard P. Riney Canine Health Center. Dog crates: when to use them and how to pick one: adult size for puppies, dividers, the bed and toilet split, larger crates for house-trained dogs.
General information, not veterinary advice. Nobody at LoveMyPuppy is a veterinarian. We read these pages in October 2026.