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Why it matters: Falls short of Claude Opus 4 on the hardest reasoning and research-grade coding tasks
Available from: Pro
Why it matters: Output pricing of $15 per million tokens is higher than open-weight alternatives like DeepSeek or Llama-based hosts
Available from: Pro
Why it matters: Extended thinking mode can substantially increase latency and token costs if not carefully gated
Available from: Pro
Why it matters: 200K context window is smaller than Gemini 2.5 Pro's 1M+ token context for very large codebases
Available from: Pro
Why it matters: Free Claude.ai usage has rate limits that make heavy iterative coding impractical without an API key or paid plan
Available from: Pro
Claude Sonnet 4 is priced at $3 per million input tokens and $15 per million output tokens through the Anthropic API, Amazon Bedrock, and Google Cloud Vertex AI. Prompt caching can reduce input costs by up to 90% and batch processing offers a 50% discount for non-real-time workloads. This pricing is unchanged from Claude Sonnet 3.7, so the upgrade comes at no additional cost. For casual use, Claude.ai offers a free tier, with Pro ($20/month) and Team ($25/user/month billed annually, or $30/user/month billed monthly) plans for higher limits.
Claude Opus 4 is Anthropic's flagship model designed for the most complex, long-running agentic tasks. It costs $15/$75 per million input/output tokens â five times more expensive than Sonnet 4 â and is built for problems where additional compute and capability materially improve outcomes. Sonnet 4 is the workhorse model: 72.7% SWE-bench Verified, identical hybrid reasoning capabilities, but optimized for high-volume production use at $3/$15 per million tokens. Most teams deploy Sonnet 4 for everyday coding agents and reserve Opus 4 for hard problems or research workflows where the extra capability justifies the cost premium.
On SWE-bench Verified, Claude Sonnet 4 scores 72.7%, which is competitive with or ahead of GPT-4.1 and Gemini 2.5 Pro on most agentic coding benchmarks. Sonnet 4's strength is instruction-following and reduced reward-hacking on long-running coding tasks, which is why GitHub chose it to power Copilot's new coding agent. Gemini 2.5 Pro retains an advantage on extremely large contexts (1M+ tokens) and GPT-4.1 has stronger general-purpose chat polish, but for autonomous coding work Sonnet 4 is currently the most reliable mid-tier option. Based on our analysis of 870+ AI tools, it's the most-recommended model for IDE-integrated agents.
Extended thinking is a hybrid reasoning feature that lets Claude Sonnet 4 deliberate for longer before responding, optionally using tools like web search between reasoning steps. You enable it via an API parameter or toggle in Claude.ai. Use it for hard problems â multi-step debugging, math-heavy reasoning, complex refactors, or research tasks â where a few extra seconds of latency and additional token spend are worth a substantially better answer. For routine code completion or quick Q&A, the default near-instant mode is faster and cheaper.
Yes â Claude Sonnet 4 powers GitHub Copilot's coding agent, Cursor's agent mode, Windsurf, Replit Agent, and dozens of other production developer tools. Anthropic has specifically tuned the model for long-horizon agentic workflows, with parallel tool use, improved memory when given file system access, and a 65% reduction in shortcut-taking behavior versus Sonnet 3.7. It is available via the Anthropic API as well as Amazon Bedrock and Google Cloud Vertex AI for enterprises with cloud-vendor preferences or compliance requirements.
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Last verified March 2026