Claude is Anthropic's family of conversational AI models, launched in 2023 and now (2026) widely considered one of the strongest options for long-document reasoning, careful writing and software development. The flagship as of 2026 is Claude Sonnet 4, with a smaller fast variant (Haiku) and a more powerful but slower variant (Opus 4.x).
Anthropic positions Claude around three differentiators:
- Long context windows — up to 1M tokens on the latest releases, suitable for analysing entire books or large codebases in one shot.
- Constitutional AI alignment — a safety training methodology where the model is taught to follow a written set of principles, producing markedly fewer harmful outputs than typical RLHF.
- Coding strength — Claude has dominated the SWE-Bench leaderboard for most of the last two years, and Claude Code (Anthropic's CLI for coding) is widely used by professional developers.
The product surface in 2026:
- Claude.ai — web and mobile chat, with Projects (workspaces with persistent context), Artifacts (live preview of generated code/docs), and Computer Use (the model controls a sandboxed desktop).
- Claude API — paid endpoints used by thousands of products, including Cursor, Notion AI, Zapier and many internal enterprise tools.
- Claude in AWS Bedrock and Google Cloud Vertex — for enterprises that need data residency in their existing cloud.
- Claude Code — the official CLI for coding tasks; runs locally, uses your own API key, can read/edit files and run commands.
For a US business team in 2026, Claude is often the choice when work involves long documents, careful tone (legal, healthcare, customer-facing copy), or serious coding. ChatGPT and Gemini both compete hard; multi-vendor strategies remain common because each provider leads on different tasks at different times.
A practical note: Claude tends to be more conservative than GPT in refusing edge-case requests and more verbose by default. Both are tuneable through the system prompt. Teams switching from ChatGPT often need to rewrite prompts because what worked for one model overcorrects on the other — the "Claude is too cautious" or "Claude is too long" complaints almost always trace back to a prompt that was tuned against GPT.