Chat / reasoning (most capable)
Claude Opus
Best for: Complex analysis, difficult coding, long agentic tasks
The most intelligent tier; best when quality matters more than speed or cost.
AppAPI
🇺🇸 United States · USA
Anthropic (Claude) models explained
Anthropic builds the Claude family of AI models, known for careful writing, long-document understanding, strong coding and a focus on safety. Models come in three tiers — Opus, Sonnet and Haiku — refreshed in new generations.
All model families
Chat / reasoning (balanced)
Claude Sonnet
Best for: Everyday work, coding, writing at scale
The balanced tier most people and businesses use by default.
AppAPI
Chat (fast / low cost)
Claude Haiku
Best for: Real-time apps, high volume, sub-agents
The fastest and most affordable tier.
AppAPI
Reasoning mode
Extended thinking
Best for: Maths, planning, hard problems
A mode where Claude reasons step by step before answering.
AppAPI
Agentic coding tool
Claude Code
Best for: Working across whole codebases
Terminal and IDE coding agent built on Claude models, with Skills, plugins and sub-agents.
App
Model names and versions change often. Check the official documentation for the newest releases.
⚡ Which model should you use?
- Default choice: Sonnet.
- Hardest problems or long autonomous tasks: Opus.
- Fast, cheap, high-volume: Haiku.
Data, privacy and your region
US providers offer business and enterprise plans with data-processing agreements, and some offer regional data residency (including in the EU/UK). Check the plan’s data-use and retention settings before sharing sensitive information.
Frequently asked questions
What is the difference between Opus, Sonnet and Haiku?
They are capability tiers: Opus is the most capable, Sonnet balances quality and cost, and Haiku is the fastest and cheapest.
What are Claude Skills?
Folders of instructions and files that teach Claude a repeatable workflow; Claude loads them automatically when relevant. See our step-by-step Skills lesson.