Anthropic

Claude 4.5 Opus

Anthropic

Claude 4.5 Opus is the most intelligent and capable model in the Claude 4.5 family, designed for the most demanding reasoning, research, and coding tasks. It introduces a unique 'effort' parameter (low, medium, high) that allows users to control the depth of the model's reasoning process and token usage. Opus 4.5 excels in handling ambiguity, complex problem-solving, and deep analysis, often succeeding where other models fail on multi-system bugs or intricate research questions. It is priced to be more accessible than previous Opus generations while delivering state-of-the-art performance.

Claude 4.5 Haiku

Anthropic

Claude 4.5 Haiku is the fastest and most cost-efficient model in the Claude 4.5 family, designed to deliver near-frontier intelligence with low latency. It is optimized for high-volume tasks, real-time responses, and sub-agent orchestration. Despite its smaller size, it supports advanced features like 'extended thinking' and computer use, making it suitable for parallelized workflows where speed is critical. It is positioned as a drop-in replacement for previous mid-tier models with significantly better economics.

Claude 4.5 Sonnet

Anthropic

Claude 4.5 Sonnet is a high-intelligence frontier model designed for complex agentic workflows, coding, and computer use. It balances capability with speed and cost, positioning it as the workhorse of the Claude 4.5 family. It features 'extended thinking' capabilities (beta) and is optimized for long-horizon tasks, capable of maintaining focus for extended periods (up to 30+ hours in internal tests). It introduces significant improvements in tool use, particularly in interacting with software interfaces and executing complex multi-step plans.

Claude Opus 4

Anthropic

Claude Opus 4 is Anthropic's most powerful model and the best coding model in the world, leading on SWE-bench (72.5%) and Terminal-bench (43.2%). It delivers sustained performance on long-running tasks that require focused effort and thousands of steps, with the ability to work continuously for several hours. Features include extended thinking with tool use, parallel tool execution, improved memory capabilities, and significantly reduced shortcut behaviors.

Claude Sonnet 4

Anthropic

Claude Sonnet 4 significantly improves on Sonnet 3.7's capabilities, excelling in coding with a state-of-the-art 72.7% on SWE-bench. The model balances performance and efficiency, with enhanced steerability for greater control over implementations. Features include extended thinking with tool use, parallel tool execution, improved instruction following, and significantly reduced shortcut behaviors.

Claude 3.7 Sonnet

Anthropic

Anthropic's most intelligent model to date and the first hybrid reasoning model on the market. Claude 3.7 Sonnet can produce near-instant responses or extended, step-by-step thinking that is made visible to the user. API users have fine-grained control over how long the model can think for (up to 128K tokens). Priced at $3 per million input tokens and $15 per million output tokens at launch, including thinking tokens.

Claude 3.5 Haiku

Anthropic

Anthropics fastest model at time of launch, delivering intelligence at blazing speeds. Claude 3.5 Haiku is optimized for quick responses while maintaining high quality.

Claude 3.5 Sonnet

Anthropic

Claude 3.5 Sonnet raises the industry bar for intelligence, outperforming competitor models and Claude 3 Opus on a wide range of evaluations, with the speed and cost of a mid-tier model. It operates at twice the speed of Claude 3 Opus.

Claude 3 Haiku

Anthropic

Anthropic's fastest and most compact model at the time of launch with near-instant responsiveness. Answers simple queries and requests with unmatched speed while maintaining good quality. Pricing at launch: $0.25 per million input tokens, $1.25 per million output tokens.

Claude 3 Opus

Anthropic

Anthropic's most intelligent model at release, with best-in-market performance on highly complex tasks. It can navigate open-ended prompts with remarkable fluency and human-like understanding. Pricing at launch: $15 per million input tokens, $75 per million output tokens.

Claude 3 Sonnet

Anthropic

Anthropic's balanced model that strikes an ideal balance between intelligence and speed for enterprise workloads. Delivers strong performance at a lower cost compared to its peers. Pricing at launch: $3 per million input tokens, $15 per million output tokens.

Claude 2.1

Anthropic

Major update to Claude 2 featuring an industry-leading 200K token context window (roughly 150,000 words or 500+ pages), 2x reduction in hallucination rates, system prompts support, and beta tool use capabilities for API integration.

Claude 2

Anthropic

Anthropic's most capable system at release, representing a continuous evolution from previous Claude models. Trained via unsupervised learning, RLHF, and Constitutional AI with both supervised and reinforcement learning phases. Features improved helpfulness, honesty, and harmlessness (HHH) with enhanced coding abilities, longer output generation up to 4000 tokens, and better structured data formatting capabilities.

Claude (v1)

Anthropic

Anthropic's first-generation AI assistant, built on research into training helpful, honest, and harmless AI systems. Claude was designed for conversational and text processing tasks with enhanced safety features, reduced harmful outputs, and improved steerability compared to earlier language models. Claude v1 introduced Constitutional AI training methods that became foundational to Anthropic's approach.