About this website.
A short, sincere account of what IsMyCatFat is, who's behind it, and the deal we're offering you.
IsMyCatFat is a small, free, ad-supported website that judges photographs of cats. You upload a cat. An AI gives you a verdict on a five-tier scale, from Svelte to Absolute Unit, with a roast attached. You laugh, share, possibly think about your cat's diet, and move on.
That's the whole product. There is no app to download, no account to create, no premium tier we're pushing you toward, no email funnel that ends with a $97 e-book. We genuinely just judge cats.
Why does this exist?
Three reasons, in honest order.
One: it's funny. The chonk meme is a small but lovely piece of internet culture, and turning it into something interactive felt natural. There was no website that did this well. Now there is.
Two: roughly 60% of pet cats are overweight, according to the Association for Pet Obesity Prevention, and most owners don't notice because they see their cat every day. A site that's funny and useful — that gives owners a moment of pause to think about whether their cat might be in a higher tier than they realised — does some real good. The roast is the door; the body condition science is the room behind it.
Three: we wanted to make something that paid for itself. The site is supported by ads. If enough cats get judged, the ads cover hosting and the AI processing costs, and a little extra goes to the person who built it. This is a very modest goal, and we've tried to be transparent about it instead of pretending the site is a charity.
The deal we're offering.
Every free website on the modern internet is offering a deal — usually one that isn't spelled out. Ours is:
- Judge your cat for free, no account required
- Never store the photos you upload
- Show ads (Google AdSense) to cover costs
- Tell you exactly what data flows where in our privacy policy
- Maintain the site as long as it pays for itself
- Reply to emails, sent by humans, written by humans
- Update content (especially the body condition guide) as veterinary understanding evolves
- Sell your data to third parties
- Train AI models on your cat photos
- Add a paywall or "Pro" tier later as a bait-and-switch
- Run pop-ups, modal newsletters, or interstitial ads
- Send you marketing emails unless you specifically signed up for the digest
- Pretend we're not advertising-funded
- Claim to give actual veterinary advice
Honest about the AI.
The verdicts on this site are produced by Claude, a large language model made by Anthropic. We send the model your photo, ask it to assess the cat using clear instructions, and pass its response back to you. We don't pre-write the roasts; the model writes a fresh one each time. This means:
- ▸The verdicts are generally consistent but not perfectly so. The same cat might get tier 3 once and tier 4 the next time. That's why we built the "roast my cat differently" button — variation is a feature.
- ▸The model occasionally misjudges fluff for fat or vice versa. Long-haired cats sometimes get bumped up a tier they don't deserve. We've tuned the prompt to account for this, but it's not perfect.
- ▸The verdicts are not veterinary advice. We say this in the disclaimer below every result, in the privacy policy, in the body condition guide, and now here for the fourth time. If you're genuinely worried about your cat's weight, your vet is the right person to talk to.
Who built this?
IsMyCatFat is built and operated by an individual, not a company. There's no team, no investors, no marketing department. The site runs on Cloudflare's free tier and Anthropic's API, with the small revenue from Google AdSense covering costs and (we hope) eventually paying for the time spent maintaining it.
This means:
- ▸If you email us, you're emailing a person. Replies come from that person, not a ticket system.
- ▸If something breaks, the same person fixes it, usually within a day if we're around.
- ▸If we ever decide the site isn't worth maintaining, we'll say so on this page rather than letting it rot.
- ▸If we ever sell the site, we'll keep this section honest about the change.
We don't post a name here for the same reason most one-person projects don't: this isn't a personal brand, it's a useful chaotic website about cats. If you need to know who you're dealing with for legal or business reasons, email us and we'll tell you.
What might be coming.
We have ideas. None of them are promises, but if you're curious where this is heading:
- ▸A breed-specific tier, where the model knows that a Maine Coon at 18lbs isn't the same as a Siamese at 18lbs.
- ▸A "judge me, not just the cat" mode, where the AI also roasts the photographer.
- ▸Multi-cat verdicts, where you upload a photo of three cats and get a tier for each, ranked.
- ▸A real public Hall of Shame with opt-in cat submissions, which would replace the seeded examples currently on the homepage.
- ▸More guides — cat weight by breed, exercise routines for indoor cats, what your cat's preferred sleeping position says about its insurance premiums (we're joking about that last one. Probably).
What we're not planning: a paid tier, an app, push notifications, "AI cat coaching", NFTs, a Discord server, or anything else that would compromise the simple deal of a free, fast, occasionally-funny tool that judges your cat.
Press inquiries, feedback, partnerships, complaints, your cat's contribution to the Hall of Shame, or just to say hi: hello@mycatisfat.com.
If you're a vet and you spot something inaccurate in our body condition guide, please especially get in touch. We'd rather correct it than be wrong.