· Model provider/ Head to head

Anthropic vs OpenAI

Both are commercial model provider options with comparable terms, so the choice comes down to which model of the problem you prefer — compare the descriptions below rather than the licence.

Anthropic

Claude Opus, Sonnet and Haiku. Strong tool use and long-horizon agentic work.

Proprietary · usage based · hosted service only · SDKs for TypeScript and Python

Enable prompt caching on the system prompt and tool definitions — it is the single biggest cost lever.

OpenAI

GPT and o-series via the Responses API.

Proprietary · usage based · hosted service only · SDKs for TypeScript and Python

· Side by side/ 2 of 6 differ
AnthropicOpenAI
LicenceProprietaryProprietary
Pricingusage basedusage based
Self-hostableNoNo
LanguagesTypeScript, PythonTypeScript, Python
Installnpm install @anthropic-ai/sdknpm install openai
Keys requiredANTHROPIC_API_KEYOPENAI_API_KEY
· Common questions/ FAQ

What is the difference between Anthropic and OpenAI?

Both are commercial model provider options with comparable terms, so the choice comes down to which model of the problem you prefer — compare the descriptions below rather than the licence. Anthropic: Claude Opus, Sonnet and Haiku. Strong tool use and long-horizon agentic work. OpenAI: GPT and o-series via the Responses API.

Can Anthropic and OpenAI be self-hosted?

Anthropic is a hosted service only. OpenAI is a hosted service only.

Are Anthropic and OpenAI open source?

Anthropic is proprietary (usage based). OpenAI is proprietary (usage based).

Build a stack with AnthropicAll model provider options
· For agents/ This page, machine-readable

Every page here answers to Accept: text/markdown and returns the same content at roughly a tenth the tokens. No separate site, no toggle — same URL.

curl -s -H "Accept: text/markdown" https://newagent.build/compare/anthropic-vs-openai