Claude 4 Full Series Deep Dive: Opus 4, Sonnet 4 Capabilities and Usage Guide
Anthropic has officially released the Claude 4 series, including Opus 4 (top-tier reasoning) and Sonnet 4 (high cost-performance). This article provides an in-depth analysis of the core capability improvements of both models, comparisons with the previous generation, real-world performance, and guidance on which model to choose for different scenarios.
Quick Answer
The three most important upgrades in Claude 4:
- Extended Thinking 3.0: Significantly improved reasoning depth, with math/coding benchmarks exceeding 95%
- 200K→500K Context: Opus 4 supports 500K tokens, equivalent to 400 pages of PDF
- Tool Call Stability: Multi-tool concurrent call success rate increased to 98%, with notable improvement in agent task completion
Claude 4 Release Background
In May 2026, Anthropic officially launched the Claude 4 series at its annual developer conference, about 10 months after the Claude 3.5 series. This is the largest model upgrade in Anthropic's history, with simultaneous releases of:
- Claude Opus 4 (flagship reasoning model)
- Claude Sonnet 4 (high cost-performance workhorse)
- Claude Haiku 4 (ultra-fast lightweight model)
- Claude Code 2.0 (coding agent designed for developers)
Opus 4 vs Sonnet 4: How to Choose
| Aspect | Opus 4 | Sonnet 4 |
|---|---|---|
| Positioning | Top-tier reasoning, complex tasks | Daily workhorse, cost-effective choice |
| Context | 500K tokens | 200K tokens |
| Speed | Moderate (deep thinking) | Fast (2-3x) |
| Price | $15/M input tokens | $3/M input tokens |
| Best for | Math proofs, long document analysis, complex code refactoring | Daily writing, code generation, conversation |
Recommendation: 90% of daily tasks can be handled by Sonnet 4; only tasks requiring deep reasoning (research reports, complex algorithm design) need Opus 4.
Benchmark Data
| Benchmark | Claude 3.5 Sonnet | Claude Sonnet 4 | Claude Opus 4 |
|---|---|---|---|
| SWE-bench | 49% | 62% | 74% |
| MATH | 71% | 83% | 92% |
| GPQA | 59% | 68% | 78% |
| HumanEval | 92% | 95% | 97% |
Key Changes for Developers
API Level
- New
thinking_budgetparameter (controls reasoning depth, balancing cost and quality) - Tool calls support streaming output (significantly reduces time-to-first-token)
- New
computer_use_2.0tool type (enhanced interface manipulation capability)
Claude Code 2.0
- Supports simultaneous understanding of multiple code repositories (up to 5 repos)
- New "Planning Mode": outputs a complete modification plan first, then executes after user confirmation
- Test-driven development: automatically generates tests → runs them → modifies code based on failures, iterating in a loop
Common User Feedback (First Week After Release)
Positive:
- "Sonnet 4's coding ability is noticeably stronger than 3.5, with higher one-shot generation success rate"
- "Extended Thinking provides clearer steps for math problems, significantly reducing error rates"
Areas for Improvement:
- "Opus 4 is expensive; medium tasks don't need it"
- "Image generation still relies on third parties; hope for native image capabilities"
FAQ
Q: Can I still use Claude 3.5 Sonnet? A: Yes, Anthropic promises to support it for at least 12 months. However, from a cost-performance perspective, Sonnet 4 offers similar pricing with stronger capabilities, so gradual migration is recommended.
Q: Has Claude 4 improved Chinese language support? A: Yes, significantly. Chinese comprehension accuracy has improved by about 15%, and generated Chinese text is more natural and fluent, with fewer awkward translation artifacts.
Related Resources
- AI Model Comparison: aiskillnav.com/models
- Claude Code Usage Guide: aiskillnav.com/tutorials/claude-code-vs-cursor-2026-complete-comparison
Also available in 中文.