About PetSizeCalc

Why this site exists

Buying gear for a dog or a cat runs into the same wall every time: the thing you can measure at home is not the thing the shop asks for. You can measure your dog. You cannot measure "medium".

Size names are not standard. A medium harness from one brand is a large from another. A crate is sold by length in inches while the dog is described by weight. A food bag gives a daily amount for a weight range that may not include your dog.

So every tool here does one job: it takes the measurement you actually have, and converts it into the number that the product page wants, using a method you can check.

Where the numbers come from

We keep two kinds of figure apart, and label which is which on the page:

Published figures

Breed weights come from the American Kennel Club. Crate lengths follow the crate lengths MidWest Homes for Pets publishes for its own crate line; the weight bands that pair a weight with one of those lengths are our own estimate, and the pages say so. Feeding timelines come from the AKC. The calorie range is reproduced from the WSAVA guidance. Cat age uses the International Cat Care table. Where a source disagrees with itself or with another body, the page says so rather than picking one silently.

Our own working

Some things no one publishes. Mapping a breed's weight range onto a crate length is our own step on top of a manufacturer's crate lengths. "Common range" tables and fit checks are ours. Those are labeled as ours, and the page usually shows the arithmetic so you can re-run it.

What we deliberately do not do

• We do not give veterinary advice. These are measuring and sizing tools. Anything about your individual animal's health belongs with your vet.
• We do not publish a feeding amount of our own. The feeding table on your own bag wins; our job is to split its number into meals.
• We do not show live prices. We link to a shop search instead, so you are never shown a stale figure.
• We do not guess a size from a breed. If a tool needs a measurement, it asks you for the measurement.
• We do not sell or share anything you type. Nothing you enter is sent to us — see the privacy policy.

How this site is written and checked

PetSizeCalc is an independent tool site, written and maintained by its owner. It is not run by a veterinary practice, a shop or a brand — which is also why there are no prices on the site and no sponsored posts.

Who writes it

One person writes and updates the pages. Where a figure comes from an organization, the page names the organization and links to it. Where a figure is our own working margin, the page says so in that section instead of presenting it as a standard. That pattern is on every tool page, and the sources sit at the bottom of each one.

What “checked” means here

Before a page goes live it is re-read against its sources, and quoted figures are compared with the current wording on the organization’s own site — the American Kennel Club, the Humane Society of the United States, WSAVA, AAFCO and International Cat Care. Where no source could be found, the claim was either removed or labelled as our own estimate. We do not fill gaps with plausible-sounding numbers.

How often it is reviewed

Sources are re-checked whenever a page changes, and the whole site was last checked against its sources on October 19, 2026. Each page carries a “Last updated” date so you can see how old the text is.

What we are not

We do not diagnose, treat or prescribe, and we do not publish a feeding amount of our own — the feeding table on your bag wins. Anything about your dog’s health, weight or diet belongs with your vet.

If a figure looks wrong, tell us. The page and the figure are enough, and we will check it against the source and correct the page.

Contact

Found an error, or a number you think is wrong? That is the most useful thing you can send us. Email petsizecalc@gmail.com.

If you are reporting a wrong figure, the page and the figure are enough — we will check it against the source and correct the page.