The AI that thinks deeply

Claude 3.7 Sonnet is Anthropic's most capable model, and in 2026 it's the default choice for tasks that require careful reasoning — code review, long-form writing, legal analysis, research synthesis. The 200K context window means you can paste entire books and ask nuanced questions. The 'thinking' mode in 3.7 lets the model spend more compute on hard problems, dramatically improving accuracy on math and logic.

Who it's for: Writers, researchers, developers, and analysts who need careful, accurate AI assistance. The default for any task where ChatGPT feels too 'fast and loose.'

Key features

🧠Extended Thinking

Toggle 'thinking mode' for harder problems. Claude spends more compute, gives more accurate answers.

📚200K Context

Paste entire books, codebases, or research papers. Claude maintains coherence across 200,000 tokens.

💻Claude Code

Anthropic's official coding agent. Reads your codebase, makes multi-file changes, runs tests.

🎨Artifacts

Interactive documents Claude creates alongside chat. Code that runs, designs that render.

The honest take

✓ What works

Most accurate AI on complex reasoning tasks
200K context window — far larger than ChatGPT's 128K
Claude Code is the most capable AI coding agent
Artifacts create an actual workspace, not just chat
Constitutional AI — fewer jailbreaks, more reliable safety

✗ What doesn't

Slower than GPT-4o for casual conversation
Less multimodal than ChatGPT (no native image generation)
No voice mode (ChatGPT has this)
$20/mo same price as ChatGPT Plus

Verdict

The default for writing, analysis, and code. Use ChatGPT for casual conversation, image generation, and voice. Use Claude for everything that requires careful thought or long context.