AI models explained (2026): the brains behind the apps
ChatGPT, Gemini, Claude… Some of these names are apps and some are models. Here's the difference in plain English, and a one-page guide to the big seven.
Research-based, not tested. Written from official pages and help docs (last checked Oct 15, 2026). We haven't run our own tests of this yet, so treat it as an explainer, not a verdict. How we test
Model vs app: what's the difference?
An AI model is the “brain”: software trained on huge amounts of text and images that predicts good answers. An app is what you actually open and type into. It wraps a model with extras like voice, memory, image creation and web search.
- ChatGPT is an app; it runs OpenAI's GPT models.
- Gemini is both Google's app and its model family.
- Claude is both Anthropic's app and its models.
- Llama is just a model: Meta lets anyone download it, and other apps build on it.
So when you pick an AI, you're really picking two things: how smart the model is, and how useful the app around it is.
Latest releases (last checked Oct 15, 2026)
- Gemini 4 Argon Good at: Google’s newest flagship, now in the Gemini app for Google AI Pro and Ultra
- Muse Wonder Good at: Meta’s most capable models: a new Muse family, separate from Llama
- GPT-6 (rollout) Good at: Everyday writing, explaining and brainstorming in ChatGPT
- Mistral Large 4 Good at: Mistral’s newest model, in public preview, with open weights promised
- GPT-6.1 Sol Good at: Near-Astra intelligence at lower cost, in ChatGPT Work and Codex
- Claude Sonnet 5.5 Good at: 30%+ faster than Sonnet 5; long, careful writing and editing
- GPT-6 Sol & Luna Good at: Luna powers free ChatGPT’s everyday chats
- Claude Opus 5.5 Good at: Anthropic’s recommended starting point for most work
- Grok 4.7 Good at: Live search of the web and X for what’s happening now
- DeepSeek-V4.1-Flash Good at: Understands images as well as text; free in the DeepSeek app
- GPT-6 Astra Good at: OpenAI’s most intelligent model (paid plans)
- Claude Fable 5.1 Good at: Anthropic’s most capable model (paid plans)
Newest first. Each card opens our page for that model. Dates are from each company's own announcements. Release dates for Claude Haiku 5.5 and Mistral Medium 3.5 couldn't be confirmed.
The big seven at a glance (as of Oct 15, 2026)
| Model | Made by | Best known for | Free? | Paid |
|---|---|---|---|---|
| GPT (ChatGPT) | OpenAI | The best-known all-rounder | Yes, unlimited everyday chats | $8–$500/mo |
| Claude | Anthropic | Careful writing and coding | Yes (Sonnet, Haiku) | $17–$20/mo Pro |
| Gemini | Built into Google apps and Android | Yes (Flash-Lite) | $4.99–$199.99/mo | |
| Llama | Meta | Free models to run yourself | Free download | n/a |
| Mistral | Mistral AI | European, low-cost, open-weight | Yes (limited) | $14.99/mo Pro |
| DeepSeek | DeepSeek | Free app, cheap API | Yes (app is free) | API only |
| Grok | xAI | Live news from the web and X | Yes (daily limits) | $8–$200/mo |
Start here
Which AI model should I use?
Match a model to what you want to do.
Best free AI models
What you get without paying.
ChatGPT vs Claude
Two popular assistants side by side.
ChatGPT vs Gemini
The two biggest names compared.
AI on your phone
Apple Intelligence, Gemini on Android and more.
A few words you'll see
- Open-weight: the model can be downloaded and run on your own computer (Llama, Mistral's Medium 3.5).
- Context window: how much text the AI can “keep in mind” at once.
- Reasoning or “thinking” models: slower models that work through hard problems step by step.
- API: how developers plug a model into their own apps, usually paid per use.
Sources
- ChatGPT pricing: last checked Oct 2026
- Claude pricing: last checked Oct 2026
- Gemini subscriptions: last checked Oct 2026
- Meta: The Llama 4 herd: last checked Oct 2026
- Mistral pricing: last checked Oct 2026
- DeepSeek download page: last checked Oct 2026
- xAI docs: X Subscription pricing: last checked Oct 2026
Prices and plans change often. Always confirm on the official site before you buy.
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