Tool & Platform
Beginner
OpenAI · Tools & API Platforms
OpenAI's conversational product — the free tier is enough to try mainstream model capabilities, and it is most people's first stop with AI.
Tool & Platform
Beginner
Anthropic · Tools & API Platforms
Anthropic's conversational product, well regarded for long context and coding; the free tier works for daily use.
Tool & Platform
Beginner
Perplexity · Tools & API Platforms
An AI-native search engine whose answers cite sources — handy for quickly verifying questions that come up while studying.
Tool & Platform
Intermediate
Groq · Tools & API Platforms
Groq's inference cloud runs open models at extreme speed, with free credits on signup.
Tool & Platform
Beginner
Google · Tools & API Platforms
Google's model playground: call Gemini models and debug prompts right in the browser, with a friendly free tier.
Tool & Platform
Intermediate
OpenRouter · Tools & API Platforms
A unified LLM API gateway — one key for hundreds of models, some of them free.