OpenAI API vs Anthropic API: Which LLM API to Choose?
Compare the OpenAI API and Anthropic API on models, cost, speed, and safety. Discover which LLM API best fits your chatbot.
OpenAI API
The most widely used LLM API in the world with GPT-5, GPT-4o, Assistants API, embeddings, and fine-tuning capabilities.
Anthropic API
Anthropic's API with Claude Opus, Sonnet, and Haiku — focused on safety, longer context, and nuanced responses.
Comparison table
| Feature | OpenAI API | Anthropic API |
|---|---|---|
| Models | GPT-5, GPT-4o, GPT-5 mini, embeddings | Claude Opus, Sonnet, Haiku |
| Context window | Up to 128K tokens | Up to 200K tokens |
| Ecosystem | Broadest — Assistants, function calling, vision, audio | Growing — tool use, vision, computer use |
| Safety | RLHF with guardrails | Constitutional AI — extra focus on safety |
| Cost (per token) | GPT-5 mini very affordable | Haiku very affordable, Sonnet competitive |
Verdict
Both APIs are excellent for chatbot applications. OpenAI offers the broadest ecosystem, Anthropic the best safety guarantees and longer context. Prices are comparable. Test both for your specific use case.
Our recommendation
OpenClaw Installeren supports both APIs. We configure Claude Sonnet by default for the best balance between quality, safety, and cost. Want GPT-5? That's one configuration change. The advantage of OpenClaw is that you're not locked into a single provider.
Frequently asked questions
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