Ptero is a free, open-source AI chat platform that gives developers access to dozens of language models without a paid subscription.
What is Ptero?
Ptero.pro is a free, non-profit chat platform where users can talk to a wide range of AI models including Claude, DeepSeek, Qwen, MiniMax, and Mistral. It runs entirely in the browser with no server-side conversation storage, and users can start chatting instantly as a guest or logged-in WordPress user.
Key Features
- Model variety — Access dozens of models (Claude Opus 4.8, DeepSeek V4, Qwen3.7 Max, MiniMax M2.7, Mistral Large 3, etc.) all free of charge.
- GitHub unlock — Star the Ptero repository on GitHub to unlock premium models like Claude Opus 4.8 and Claude Haiku 4.5.
- Local storage privacy — Conversations are stored in your browser's local storage; the server does not keep a copy of chat history.
- Anonymous usage — Only anonymous usage counters and per-model vote tallies are kept, with no message content.
- Attachments — Attach images, files, or a GitHub repository URL to give the AI context.
- Projects — Organize related chats into named projects.
- Code editor and preview — Built-in code editor with file download and preview capabilities.
- Open source — Fully open source; source code available on GitHub.
Who is it for?
- Developers — Test different AI models and compare outputs without cost, using the code editor for snippets.
- Students — Experiment with multiple LLMs for learning and homework help with no budget.
- AI enthusiasts — Explore new and niche models like Mercury 2 or SenseNova without signing up for separate services.
Use cases
- Model comparison: Run the same prompt across several models (e.g., DeepSeek V4 Pro vs Qwen3.7 Max) to compare quality and speed.
- Code development: Attach a GitHub repo or paste code for debugging, refactoring, or code generation with models like Codestral or Qwen3 Coder Plus.
- Content generation: Use any of the available LLMs for writing, summarization, or brainstorming, with conversations saved locally.
- Privacy-focused research: Have discussions knowing your chat history stays in your browser and is not stored on the server.
How does Ptero work?
To start, pick a display name (saved on your device), accept the terms, and choose a model from the list. Each message is transmitted to the selected third-party provider, which generates a response; the conversation is saved to your browser's local storage. No account is required for guest access, and you can attach files, images, or GitHub repositories to provide context.
Pricing
Ptero is completely free with no premium plans, subscriptions, or paywalls. All models are available at no cost; some models require starring the GitHub repository to unlock, but this is also free.
FAQ
Is Ptero really free forever?
Yes, the terms state it is "completely free to use and will always be free." The service does not offer paid plans and promises not to introduce them.
Are my chats stored on the server?
No, conversations are saved only in your browser's local storage. The server relays messages to AI providers but does not write chat content to its database.
Which models are available?
The model list includes Claude Opus 4.8, Claude Haiku 4.5, DeepSeek V4 Pro/Flash, Qwen3.8/3.7 series, MiniMax M2.7, Mistral Large 3, Codestral, and many more — over 70 models total.
Do I need to create an account?
No, you can chat as a guest identified by a random token stored in your browser. You may also log in as a WordPress user if you prefer.
What is the GitHub star unlock?
Starring the Ptero repository on GitHub (free) unlocks models like Claude Opus 4.8 and Claude Haiku 4.5.
