Intelligence index
Outperforms 52% of compared models
Claude Sonnet 4
Claude Sonnet 4 significantly enhances the capabilities of its predecessor, Sonnet 3.7, excelling in both coding and reasoning tasks with improved precision and controllability. Achieving state-of-the-art performance on SWE-bench (72.7%), Sonnet 4 balances capability and computational efficiency, making it suitable for a broad range of applications from routine coding tasks to complex software development projects. Key enhancements include improved autonomous codebase navigation, reduced error rates in agent-driven workflows, and increased reliability in following intricate instructions. Sonnet 4 is optimized for practical everyday use, providing advanced reasoning capabilities while maintaining efficiency and responsiveness in diverse internal and external scenarios.
Read more at the blog post here
- Input / output price
- $3/$15per 1M tokens
- Context
- 200K
- Released
- 2025-05-22
Pricing
Artificial Analysis
Explore rankingsCoding index
Outperforms 35% of compared models
Design Arena
Elo scores and win rates across design and agent tasks.
Category performance
1,000-1,500 EloModel Arena
SVG
1078Elo
Win rate 51.1%
3D
1140Elo
Win rate 57.8%
Game Development
1142Elo
Win rate 54.8%
Data Visualization
1159Elo
Win rate 56.5%
UI Component
1130Elo
Win rate 57.9%
Code Categories
1143Elo
Win rate 53.4%
Website
1147Elo
Win rate 52.4%
Related Models
Claude Opus 5.5
anthropicClaude Opus 5.5 is Anthropic's flagship model for demanding reasoning, coding, and long-horizon agentic work, succeeding Claude Opus 5. It is particularly strong at multi-step changes in large codebases, code review and bug finding, financial and scientific analysis, and reading dense charts, diagrams, and screenshots, and it is more careful than its predecessor about only stating figures and citing sources it can back up. The model completes comparable tasks in fewer steps and with fewer tokens than Opus 5, and reports on its work in plainer language, with clear updates on what it did, what it found, and what it needs from the user. Thinking is always adaptive, so effort is the main lever for trading off depth, latency, and cost, and lower effort settings remain effective for latency-sensitive workloads.
- Context
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- Max output
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- Released
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- Input
- $4/M
- Output
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- Cache read
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Claude Sonnet 5.5
anthropicClaude Sonnet 5.5 is Anthropic's Sonnet-class model for well-scoped everyday work, succeeding Claude Sonnet 5 as a direct upgrade. It is especially strong at building features, fixing bugs, and producing polished documents, slides, and spreadsheets, and it writes and communicates more clearly than its predecessor. Thinking is always on, so effort is the main lever for trading off depth, latency, and cost, and lower effort settings keep it responsive for everyday agentic loops.
- Context
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- Max output
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- Released
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- Input
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- Output
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- Cache read
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Claude Fable 5.1
anthropicClaude Fable 5.1 improves on Claude Fable 5 across the board, with the biggest gains in agentic coding, long-running agentic workflows, and knowledge work: long code refactors, front-end and visual code generation, and finance and analysis tasks in particular. It also tends to be more concise than Fable 5 in its plans and summaries. We recommend testing it as a direct upgrade wherever you use Fable 5 today, and alongside Opus 5 on reasoning-heavy tasks.
- Context
- 1.0M
- Max output
- 128K
- Released
- 2026-09-01
- Input
- $10/M
- Output
- $50/M
- Cache read
- $0.25/M