About Paw Charts

I'm Dana Whitcomb. I'm a certified veterinary technician, and I built this site because the pet calculators people kept showing me in the exam room were doing arithmetic I'd have failed a student for.

Who I am

Twelve years in, split between two very different rooms. Seven in general practice — vaccines, dentals, the long slow conversations about weight. Five on overnight emergency, which is a different job entirely and where most of what I know about toxicology comes from. I'm based in Fort Collins, Colorado.

Certified Veterinary Technician, which means I'm the person who takes the history, runs the bloodwork, places the catheter, and explains the discharge instructions twice because nobody hears them the first time. I'm not a veterinarian. I don't diagnose and I don't prescribe, and this site does neither.

At home: Wendell, a 62 lb Labrador-hound mix I adopted at ten weeks and who appears in most of the worked examples on this site because I have seven years of his weights in a notebook. And Poppy, 11 lb, spayed, indoor, nine years old, and firmly of the view that the radiator is hers.

Why this site exists

Someone would come in worried about their puppy's size, having used a calculator that told them a 40 lb dog was heading for 90. Or they'd bring in a chocolate number that was wrong because the tool had counted theobromine and ignored caffeine. Or — the one that actually got me started — they'd have been told their overweight dog needed 1,100 calories by a tool that had quietly run the weight-loss maths on the dog's current weight instead of its ideal one, which is how you prescribe maintenance and call it a diet.

None of these tools showed their working. Not one told you where its numbers came from. And several of them were, in a very specific and checkable way, wrong.

So the rule here is simple: every number traces to a named source with a date on it. If you want to check me, how we calculate lists every formula, multiplier and threshold on the site with its source. That page is deliberately the most detailed thing here.

What I promise you

How often I check

Twice a year — every January and every July. I re-verify the whole data file against Merck, the current AAHA guidelines and WSAVA, and log what changed in the change log with the date.

Poison-control fees get checked quarterly, because they move and because the wrong number there costs someone money at the worst possible moment. Last full verification: 2026-07-16.

The baseline check found a dozen things wrong with values that are in wide circulation — including a chart everyone credits to the AVMA that the AVMA has never published, and a chocolate figure that half the internet labels as theobromine when it's actually theobromine plus caffeine. Those are all listed in the change log. I'd rather show you the corrections than pretend the first draft was right.

What I won't publish

Medication doses. Benadryl, trazodone, gabapentin, meloxicam, carprofen. It's the biggest traffic opportunity in this niche by a distance, and it isn't going on this site until a veterinarian's name is on it as reviewer. When it does, the doses will be vet-typical ranges, with contraindication warnings, framed as reference for vet-directed treatment. Never a single directive number. A website should not be the thing standing between your dog and a dosing error.

Anything that reads as "your pet is fine." The toxicity tools here output urgency states, not verdicts. The lowest state on the chocolate calculator is "monitor at home," and it still tells you what to watch for and when to call. The grape calculator has no state below "call your vet" — because there is no established safe dose of grapes, and a green light there would be a lie with consequences.

Instructions for making your dog vomit. The ASPCA's position is that doing it at home is dangerous without veterinary direction. That's their call to make and I agree with it.

Corrections

If something here is wrong, I want to know, and I'd rather hear it from you than from a reader who trusted it. A correction with a source attached beats a compliment. Send it here — it'll be fixed and logged with the date.

The honest limit

I can't examine your pet. Nothing on this site can. Every tool here is arithmetic applied to numbers you typed in, and arithmetic can't feel a dog's ribs, hear a heart murmur, or notice that a cat has stopped grooming. The most useful thing on this site is probably the sentence telling you to call your vet — the rest is just doing the sums accurately enough to be worth acting on.