Compare ChatGPT, Claude, Gemini and Grok side by side. 100% free.
Important: the only way to see the real ChatGPT, Claude, Gemini and Grok here is to add each company's own API key. Without keys, free substitute models answer — they have nothing to do with those 4 AIs.
The four AIs don’t live on this website. ChatGPT lives on OpenAI’s computers, Claude on Anthropic’s, Gemini on Google’s and Grok on xAI’s. To ask them anything you need a pass that says who is asking. That pass is the API key: a code of letters and numbers that you copy from the company’s page and paste here once.
It works like a library card: you sign up once, the card costs nothing, and after that you can ask as many questions as you want.
Every answer costs the company money, and 4in1AI is free, with no ads and no subscriptions — so there is no wallet here to pay four companies. Each person brings their own card. The key only travels to that company (never to us), and you can delete it whenever you want.
One free key — about 1 minute
You get a key from OpenRouter (a free service that hands out test models), paste it here, and the four cards answer right away. But they answer with free stand-in models: not the real ChatGPT, Claude, Gemini or Grok.
Each company’s own key — the real thing
Add OpenAI’s key and the ChatGPT card answers with the real ChatGPT. Add Anthropic’s and the Claude card answers with the real Claude. Same for Google and xAI, one at a time. Each company charges a few cents per answer (Gemini has a free tier).
You need nothing to look around: the sample comparison needs no key at all.
“Is a hot dog a sandwich? Give a verdict.”
Verdict: technically yes, culturally no.
By structure (filling inside bread) a hot dog fits the broad definition of a sandwich. But most people — and the National Hot Dog and Sausage Council — treat it as its own category.
Verdict: No.
A sandwich generally uses two separate pieces of bread. A hot dog bun is a single hinged roll, which puts it closer to a taco. Language follows usage, and almost nobody orders "a sausage sandwich".
Verdict: Yes, legally.
The USDA classifies hot dogs as a "sandwich" for labeling, and some US state tax codes do too. So in official terms the answer is yes, even if it feels wrong.
Verdict: It's a taco. Fight me. 🌭
One bread, folded, filling in the middle — that's the taco structural model. Merriam‑Webster said hot dogs are sandwiches and the internet revolted. Respect the revolt.
Super SynthesisReads the 4 answers and gives you one: what they agree on, where they disagree, unique ideas and a final best answer.
AI CouncilThe AIs judge each other: a strength and weakness for each answer, then a verdict naming the best one.
Battle cardTurns the comparison into an image (square or vertical) ready to share on social media.
Officially a sandwich, culturally its own thing. Call it a hot dog and you'll never be wrong.
4in1AI sends your question to the four best-known AI assistants at the same time: ChatGPT by OpenAI, Claude by Anthropic, Gemini by Google and Grok by xAI. Compare how each one answers, vote for the best in a blind test, and get one combined answer.
Good to know: the only way to get the real ChatGPT, Claude, Gemini and Grok is with each company's own API key. Without keys, free substitute models answer instead — they are not those 4 AIs. Add your keys in “API Keys” to unlock the originals.