Free pet calculator widgets
Add a working dog or cat calculator to your own site with one copy-paste. Free for rescues, clinics, clubs and pet blogs.
Last updated
Each widget below is the same calculator that runs on MyPetMath, in a frame you can paste into any page that accepts HTML: WordPress, Wix, Squarespace, Weebly or plain HTML. It updates automatically when we update a formula, so your page never goes stale. Under the frame the code adds a one-line courtesy credit you can keep, edit or remove. Click a preview link to try a widget before you add it.
Dog Age Calculator
Dog years to human years by size, with the life stage. Good for: Rescues, adoption pages, senior-dog resources.
Preview the widget · Full calculator with formula and sources
Cat Age Calculator
Cat years to human years and the matching life stage. Good for: Cat rescues, clinics, cat blogs.
Preview the widget · Full calculator with formula and sources
Dog Chocolate Toxicity Calculator
Theobromine dose in mg/kg from the type and amount of chocolate, with the risk level and poison-line numbers. Good for: Clinic pet-safety pages, holiday safety posts.
Preview the widget · Full calculator with formula and sources
Cat Pregnancy Calculator
Kitten due date and week-by-week milestones from the mating date. Good for: TNR groups, foster handbooks, cat rescues.
Preview the widget · Full calculator with formula and sources
Dog Heat Cycle Calculator
Likely fertile days and the next two heats from the first day of her season. Good for: Breed clubs, spay/neuter clinics, breeder resources.
Preview the widget · Full calculator with formula and sources
Widget questions
Is it really free?
Yes. There's no sign-up, no fee and no limit on page views. The widgets show no ads, set no cookies and load no analytics or tracking scripts.
Do I have to keep the credit link?
No. The line under the frame (“… by MyPetMath”) is a courtesy credit in plain HTML, outside the frame, so you can see and edit it. You're welcome to keep it as it is, reword it, add rel="nofollow" or delete it; the widget works the same either way. If you keep it, it helps your readers find the full page with the chart, the worked example and the sources.
Will it slow my page down?
No. The frame loads lazily, only when a reader scrolls to it, and each widget is a small page with no third-party scripts.
Where do the numbers come from?
Every calculator uses a published veterinary formula or guideline, such as the Merck Veterinary Manual's theobromine thresholds or normal feline gestation ranges. Our methodology page lists each one. MyPetMath is run by a non-vet and the widgets give estimates, so they always point readers to a vet for anything urgent.
Can I change the size or colours?
You can change the height and max-width values in the code. If you need something else, such as a widget for another calculator, get in touch.