List of the Top AI Models for StackAI in 2026

The Gemini Enterprise Agent Platform equips organizations with a range of pre-trained and customizable AI models suitable for diverse applications, including natural language processing and image recognition. These models leverage state-of-the-art machine learning techniques and can be fine-tuned to align with distinct business objectives. The platform facilitates a smooth integration of AI into business processes by providing adaptable model construction and deployment options. New users can take advantage of $300 in complimentary credits, which allow them to test various AI models and tailor them to their unique requirements. With its broad collection of models, the Gemini Enterprise Agent Platform serves as a robust foundation for businesses seeking to adopt innovative AI solutions and enhance their operations.

Claude Fable 5.1 is an advanced general-purpose AI model from Anthropic focused on coding, scientific research, knowledge work, business processes, and long-horizon agentic reasoning. It is the generally available counterpart to Claude Mythos 5.1, which uses the same underlying model but is offered with different safeguards for vetted cybersecurity and life sciences users. Compared with Claude Fable 5, Fable 5.1 shows stronger performance across agentic coding, research, computer use, multidisciplinary reasoning, business workflow automation, and other complex benchmarks. The model is designed to remain effective during long-running tasks that involve planning, tool use, repeated verification, code modification, research, and multi-step decision making. In software engineering scenarios, it can investigate difficult bugs, trace problems across large codebases, perform code review, and work through complex implementation tasks with less supervision. Anthropic also positions Fable 5.1 as a stronger research model, with demonstrated capabilities in scientific analysis, computational modeling, and other technically demanding workflows. Improvements to cache-read pricing reduce the cost of reusing previously processed context, making the model more economical for workflows that involve long conversations, large codebases, or repeated tool calls. Fable 5.1 introduces updated enterprise privacy and security options, including Enterprise Frontier Safeguards and zero-data-retention access for eligible customers during the rollout period. Its cybersecurity protections are designed to permit more benign defensive security work, including vulnerability discovery, while continuing to restrict higher-risk activities such as exploit development and certain penetration-testing tasks. The model is available through Claude.ai, Claude Code, Claude Cowork, the Claude API, Amazon Web Services, Google Cloud, and Microsoft Azure under the claude-fable-5-1 model identifier for API users.

Claude Mythos 5.1 signifies the latest evolution in the Mythos series of models developed by Anthropic, specifically designed for advanced applications across fields such as cybersecurity, biology, scientific research, programming, and extensive knowledge-intensive tasks. Although it is built on the same core architecture as Claude Fable 5.1, it stands out due to its distinct safety protocols: while Fable 5.1 is broadly available, Mythos 5.1 is restricted to select trusted access initiatives that incorporate specialized safeguards for cybersecurity and life sciences. This model sets a new standard for performance in autonomous coding and exhibits unmatched cyber capabilities compared to all previous Anthropic models. In the scientific research domain, Mythos 5.1 adeptly manages specialized tools and complex workflows related to molecular design, computational biology, and other technical disciplines. During Anthropic's evaluation, it successfully designed high-affinity protein binders for various targets, achieving its highest hit rate to date. Furthermore, it excelled in optimizing seven distinct open-source deep learning models that focus on protein and genomics. By advancing the limits of what can be accomplished, Mythos 5.1 is poised to play a pivotal role in shaping future research and development projects, ultimately influencing a wide array of scientific inquiries and technological innovations. Its capabilities suggest a transformative impact on how complex biological and computational problems are approached in the coming years.

Claude Opus 5.5 is Anthropic’s high-capability AI model for advanced coding, research, business work, computer use, and extended agentic tasks. It is designed to operate effectively on large and complex workloads that require planning, sustained context, tool use, verification, and multiple execution steps. In software engineering, Opus 5.5 can be used for codebase-wide migrations, debugging, audits, optimization, code review, and other long-running development projects. The model also supports knowledge-intensive work such as financial analysis, legal research, spreadsheet creation, executive presentations, data collection, and professional reporting. Anthropic reports that Opus 5.5 improves both task efficiency and serving efficiency compared with Opus 5, including lower token usage, faster output, and reduced cost on typical workloads. Its writing and communication behavior has been updated to prioritize important information, reduce unclear phrasing, and better follow requested style constraints. Opus 5.5 also includes stronger safeguards for autonomous and tool-using scenarios, including action screening, improved prompt-injection resistance, sandbox support, and vulnerability detection during code review. Anthropic applies additional safeguards to cybersecurity, biology, and model-distillation use cases, with expanded access programs available to verified organizations in certain sensitive fields. The model supports zero data retention and includes watermarking measures intended to support compliance requirements such as the EU AI Act. Developers can access Opus 5.5 through the Claude Platform using the claude-opus-5-5 model, while Claude Code and other Anthropic products can use it for interactive and agentic work. Claude Opus 5.5 is also available through Amazon Web Services, Google Cloud, and Microsoft Azure for organizations that prefer to deploy through major cloud platforms.

Claude Opus 5 is Anthropic’s advanced Opus model designed for high-value coding, knowledge work, problem-solving, automation, scientific research, and everyday AI workflows. The model is positioned as a thoughtful and proactive system that approaches the frontier intelligence of Claude Fable 5 at half the price. Anthropic says Claude Opus 5 delivers greatly improved performance for the same cost as Opus 4.8, with base pricing of $5 per million input tokens and $25 per million output tokens. The model supports effort settings that allow customers to optimize for deeper intelligence or conserve tokens for faster and cheaper results. Claude Opus 5 performs especially well on software engineering evaluations, including tasks that require debugging, code generation, root-cause analysis, test creation, and multi-step implementation. It also shows strong results on knowledge work, business automation, computer use, novel problem solving, and research-heavy tasks. Anthropic highlights that Opus 5 is better at checking its own work, iterating until it succeeds, and building supporting tools when a task requires it. The model improves on Opus 4.8 across life sciences evaluations, including structural biology, organic chemistry, bioinformatics, molecular structure inference, and protein function tasks. Claude Opus 5 includes alignment and safety protections that aim to allow beneficial cybersecurity and biology use cases while restricting riskier exploit generation, penetration testing, and certain autonomous misuse scenarios. It is available on Claude Max as the default model, on Claude Pro as the strongest model, and through the Claude API as claude-opus-5, with a Fast mode that runs around 2.5 times the default speed.

Claude Mythos 5 is Anthropic’s restricted-access Mythos-class AI model built for trusted organizations that require the highest level of Claude capability. The model shares the same underlying architecture as Claude Fable 5, but is offered with certain safeguards removed for approved use cases and vetted users. Claude Mythos 5 is designed for advanced cybersecurity, software engineering, scientific discovery, long-context reasoning, and autonomous research workflows. It is initially deployed through Project Glasswing for cyberdefenders and critical infrastructure providers. The model is intended to help security teams analyze complex systems, support defensive cybersecurity work, and protect important software environments. Claude Mythos 5 also demonstrates major potential in life sciences, where it can assist with protein design, binding-site selection, bioinformatics workflows, and research hypothesis generation. Anthropic reports that the model can carry out extended technical tasks, recover from failures, and operate with a high degree of autonomy. Its capabilities in genomics include assembling large-scale single-cell datasets and designing custom machine learning approaches for biological research. Because these capabilities may be dual-use, Anthropic limits access through trusted programs and applies a 30-day retention policy for Mythos-class traffic. The model is priced at $10 per million input tokens and $50 per million output tokens. Claude Mythos 5 helps vetted organizations apply frontier AI to critical defense, infrastructure, and scientific problems while maintaining controlled access and oversight.

Claude Fable 5 is a frontier AI model developed by Anthropic to deliver advanced reasoning, coding, research, and multimodal capabilities for enterprise and professional users. As a Mythos-class model adapted for broad availability, it combines high-level intelligence with safety-focused deployment controls. The model excels at software engineering tasks, including large-scale code analysis, migrations, debugging, architecture review, and autonomous project execution. Claude Fable 5 also demonstrates strong performance in knowledge work, helping users analyze documents, evaluate financial information, interpret charts and tables, conduct research, and generate actionable insights. Its vision capabilities enable sophisticated image understanding, visual reasoning, and screenshot-based analysis. The model supports long-context workflows and persistent memory utilization, allowing it to work effectively on extended tasks involving millions of tokens of information. Anthropic has implemented a layered safety framework that includes specialized classifiers for cybersecurity, biology, chemistry, and model distillation-related requests. When these areas are detected, requests may be handled by a different model with stricter operational controls. Claude Fable 5 is available through the Claude API and Anthropic’s product ecosystem, providing developers and enterprises with access to advanced AI-powered assistance. The model is designed to enhance productivity, accelerate research, improve software development workflows, and support complex analytical tasks. By combining powerful reasoning, multimodal intelligence, and enterprise-focused safeguards, Claude Fable 5 enables organizations to scale AI adoption responsibly and effectively.

Claude Opus 4.8 is Anthropic’s latest frontier AI model engineered to deliver advanced coding intelligence, reasoning capabilities, autonomous workflows, and enterprise-grade collaboration for developers, technical teams, and organizations building AI-powered systems. As the successor to Claude Opus 4.7, the model introduces improvements across software engineering, agentic execution, practical knowledge work, benchmark performance, and alignment behavior while retaining the same standard pricing structure. Claude Opus 4.8 is specifically optimized for complex coding tasks, large-scale workflow orchestration, long-running automation processes, and advanced reasoning scenarios where reliability, transparency, and contextual judgment are critical. One of the model’s defining advancements is its improved honesty and uncertainty awareness, making it significantly less likely to produce unsupported conclusions or overlook defects in generated code, reasoning chains, and operational outputs. Anthropic’s alignment assessments also report stronger prosocial behavior, lower rates of deceptive or unsafe actions, and improved adherence to user intent compared to earlier Opus releases. The release introduces configurable effort controls that allow users to determine how much computational reasoning the model applies to a task, enabling flexible tradeoffs between speed, token consumption, and response depth depending on workflow complexity. Claude Opus 4.8 also powers new “dynamic workflows” functionality in Claude Code, where the model can coordinate hundreds of parallel AI subagents during a single session to execute large-scale software engineering operations such as repository-wide migrations, testing workflows, and multi-step automation tasks. Anthropic further expanded the platform with lower-cost fast mode processing, enabling the model to operate at significantly higher speeds while remaining more affordable than previous high-performance configurations.

ChatGPT is an advanced AI-powered assistant designed to help users accomplish tasks, generate ideas, and improve productivity across a wide range of use cases. It enables users to perform activities such as writing, editing, coding, research, and brainstorming with ease. The platform supports both text and voice interactions, allowing users to communicate in the way that suits them best. ChatGPT can summarize meetings, analyze data, and provide actionable insights to support better decision-making. It also assists with creative tasks, including content creation, marketing strategies, and personal planning. One of its most powerful capabilities is workspace agents, which allow users to build automated systems that handle entire workflows. These agents can operate across different tools, gather information, and take actions such as updating documents, sending communications, or managing tasks without constant supervision. They can be scheduled to run recurring processes, ensuring work continues even when teams are not actively involved. Workspace agents can be shared across teams, helping organizations standardize workflows and scale best practices efficiently. Built-in governance features, such as permissions, approval checkpoints, and monitoring, ensure secure and controlled automation. ChatGPT integrates seamlessly into existing workflows, reducing the need for multiple tools and manual coordination. It supports collaboration by allowing teams to refine, edit, and manage work in real time. The platform adapts to various industries and use cases, from personal productivity to enterprise operations. By combining intelligent assistance with automation, ChatGPT enables users to focus on higher-impact work. Ultimately, it acts as a comprehensive solution for both everyday tasks and complex organizational workflows.

Claude is a powerful AI assistant designed by Anthropic to support problem-solving, creativity, and productivity across a wide range of use cases. It helps users write, edit, analyze, and code by combining conversational AI with advanced reasoning capabilities. Claude allows users to work on documents, software, graphics, and structured data directly within the chat experience. Through features like Artifacts, users can collaborate with Claude to iteratively build and refine projects. The platform supports file uploads, image understanding, and data visualization to enhance how information is processed and presented. Claude also integrates web search results into conversations to provide timely and relevant context. Available on web, iOS, and Android, Claude fits seamlessly into modern workflows. Multiple subscription tiers offer flexibility, from free access to high-usage professional and enterprise plans. Advanced models give users greater depth, speed, and reasoning power for complex tasks. Claude is built with enterprise-grade security and privacy controls to protect sensitive information. Anthropic prioritizes transparency and responsible scaling in Claude’s development. As a result, Claude is positioned as a trusted AI assistant for both everyday tasks and mission-critical work.

Our models are crafted to understand and generate natural language effectively. We offer four main models, each designed with different complexities and speeds to meet a variety of needs. Among these options, Davinci emerges as the most robust, while Ada is known for its remarkable speed. The principal GPT-3 models are mainly focused on the text completion endpoint, yet we also provide specific models that are fine-tuned for other endpoints. Not only is Davinci the most advanced in its lineup, but it also performs tasks with minimal direction compared to its counterparts. For tasks that require a nuanced understanding of content, like customized summarization and creative writing, Davinci reliably produces outstanding results. Nevertheless, its superior capabilities come at the cost of requiring more computational power, which leads to higher expenses per API call and slower response times when compared to other models. Consequently, the choice of model should align with the particular demands of the task in question, ensuring optimal performance for the user's needs. Ultimately, understanding the strengths and limitations of each model is essential for achieving the best results.

The fourth iteration of the Generative Pre-trained Transformer, known as GPT-4, is an advanced language model expected to be launched by OpenAI. As the next generation following GPT-3, it is part of the series of models designed for natural language processing and has been built on an extensive dataset of 45TB of text, allowing it to produce and understand language in a way that closely resembles human interaction. Unlike traditional natural language processing models, GPT-4 does not require additional training on specific datasets for particular tasks. It generates responses and creates context solely based on its internal mechanisms. This remarkable capacity enables GPT-4 to perform a wide range of functions, including translation, summarization, answering questions, sentiment analysis, and more, all without the need for specialized training for each task. The model’s ability to handle such a variety of applications underscores its significant potential to influence advancements in artificial intelligence and natural language processing fields. Furthermore, as it continues to evolve, GPT-4 may pave the way for even more sophisticated applications in the future.

The GPT-3.5 series signifies a significant leap forward in OpenAI's development of large language models, enhancing the features introduced by its predecessor, GPT-3. These models are adept at understanding and generating text that closely resembles human writing, with four key variations catering to different user needs. The fundamental models of GPT-3.5 are designed for use via the text completion endpoint, while other versions are fine-tuned for specific functionalities. Notably, the Davinci model family is recognized as the most powerful variant, adept at performing any task achievable by the other models, generally requiring less detailed guidance from users. In scenarios demanding a nuanced grasp of context, such as creating audience-specific summaries or producing imaginative content, the Davinci model typically delivers exceptional results. Nonetheless, this increased capability does come with higher resource demands, resulting in elevated costs for API access and slower processing times compared to its peers. The innovations brought by GPT-3.5 not only enhance overall performance but also broaden the scope for diverse applications, making them even more versatile for users across various industries. As a result, these advancements hold the potential to reshape how individuals and organizations interact with AI-driven text generation.

Mistral AI is recognized as a pioneering startup in the field of artificial intelligence, with a particular emphasis on open-source generative technologies. The company offers a wide range of customizable, enterprise-grade AI solutions that can be deployed across multiple environments, including on-premises, cloud, edge, and individual devices. Notable among their offerings are "Le Chat," a multilingual AI assistant designed to enhance productivity in both personal and business contexts, and "La Plateforme," a resource for developers that streamlines the creation and implementation of AI-powered applications. Mistral AI's unwavering dedication to transparency and innovative practices has enabled it to carve out a significant niche as an independent AI laboratory, where it plays an active role in the evolution of open-source AI while also influencing relevant policy conversations. By championing the development of an open AI ecosystem, Mistral AI not only contributes to technological advancements but also positions itself as a leading voice within the industry, shaping the future of artificial intelligence. This commitment to fostering collaboration and openness within the AI community further solidifies its reputation as a forward-thinking organization.

Grok is an AI-powered assistant developed by xAI, designed to provide real-time, context-aware, and engaging conversational experiences. It is tightly integrated with the X platform, allowing it to access live data, trending topics, and user-generated content for up-to-date insights. Grok is built to handle a variety of tasks, including research, content generation, problem-solving, and general inquiries. Its advanced language model enables it to understand complex questions and deliver accurate, thoughtful responses. Unlike traditional AI tools, Grok incorporates humor and personality, making interactions more engaging and human-like. The platform is particularly effective for tracking current events and social trends in real time. It supports both casual and professional use cases, offering flexibility for different user needs. Grok continuously improves through updates, enhancing its reasoning and conversational abilities. It is designed to be intuitive and easy to use within the X ecosystem. The integration with live data makes it highly relevant for fast-changing information environments. Security and performance are key priorities, ensuring reliable interactions. Overall, Grok represents a next-generation AI assistant focused on real-time intelligence and engaging user experiences.

Claude Sonnet 3.5 from Anthropic is a highly efficient AI model that excels in key areas like graduate-level reasoning (GPQA), undergraduate knowledge (MMLU), and coding proficiency (HumanEval). It significantly outperforms previous models in grasping nuance, humor, and following complex instructions, while producing content with a conversational and relatable tone. With a performance speed twice that of Claude Opus 3, this model is optimized for complex tasks such as orchestrating workflows and providing context-sensitive customer support.

Opus stands out as our leading model, outpacing rival systems across a variety of key metrics used to evaluate artificial intelligence, such as the assessment of undergraduate-level expertise (MMLU), graduate reasoning capabilities (GPQA), and essential mathematics skills (GSM8K), among others. Its exceptional performance is akin to human understanding and fluency when tackling complex challenges, placing it at the cutting edge of developments in general intelligence. Additionally, all Claude 3 models exhibit improved proficiency in analysis and forecasting, advanced content generation, coding, and conversing in multiple languages beyond English, including Spanish, Japanese, and French, highlighting their adaptability in communication. This remarkable versatility not only enhances user interaction but also broadens the potential applications of these models in diverse fields.

Claude Sonnet 3.7, created by Anthropic, is an innovative AI model that brings a unique approach to problem-solving by balancing rapid responses with deep reflective reasoning. This hybrid capability allows users to toggle between quick, efficient answers for everyday tasks and more thoughtful, reflective responses for complex challenges. Its advanced reasoning capabilities make it ideal for tasks like coding, natural language processing, and critical thinking, where nuanced understanding is essential. The ability to pause and reflect before providing an answer helps Claude Sonnet 3.7 tackle intricate problems more effectively, offering professionals and organizations a powerful AI tool that adapts to their specific needs for both speed and accuracy.

Claude Opus 4, the most advanced model in the Claude family, is built to handle the most complex software engineering tasks with ease. It outperforms all previous models, including Sonnet, with exceptional benchmarks in coding precision, debugging, and complex multi-step workflows. Opus 4 is tailored for developers and teams who need a high-performance AI that can tackle challenges over extended periods—perfect for real-time collaboration and long-duration tasks. Its efficiency in multi-agent workflows and problem-solving makes it ideal for companies looking to integrate AI into their development process for sustained impact. Available via the Anthropic API, Amazon Bedrock, and Gemini Enterprise Agent Platform, Opus 4 offers a robust tool for teams working on cutting-edge software development and research.

Claude Opus 4.7 represents a major step forward in AI model development, focusing on advanced reasoning, coding, and enterprise-level task execution. It improves significantly over Opus 4.6 by delivering stronger performance on complex and high-effort software engineering challenges. The model is particularly effective at managing long-running processes, maintaining consistency, and producing reliable outputs over time. Its enhanced instruction-following capabilities ensure that it interprets prompts more literally and executes tasks with greater precision. Opus 4.7 also features advanced self-checking mechanisms, enabling it to validate its own responses before completion. A major highlight is its improved multimodal support, allowing it to process high-resolution images and extract fine visual details. This capability is especially useful for tasks like analyzing technical screenshots, interpreting diagrams, and supporting computer-based workflows. The model produces high-quality professional outputs, including refined documents, presentations, and UI designs that meet business standards. It also demonstrates strong performance across industries such as finance, legal services, and data analysis. Enhanced memory capabilities allow it to retain important context across sessions, making it more efficient for ongoing projects. Opus 4.7 includes safety and alignment improvements, with systems in place to detect and block potentially harmful or restricted use cases. It introduces new controls for balancing reasoning depth and response speed, giving users flexibility based on task complexity. Widely accessible through APIs and major cloud platforms, Opus 4.7 is designed to support scalable, high-performance AI applications for modern enterprises.

Claude Sonnet 4 is a breakthrough AI model, refining the strengths of Claude Sonnet 3.7 and delivering impressive results across software engineering tasks, coding, and advanced reasoning. With a robust 72.7% on SWE-bench, Sonnet 4 demonstrates remarkable improvements in handling complex tasks, clearer reasoning, and more effective code optimization. The model’s ability to execute complex instructions with higher accuracy and navigate intricate codebases with fewer errors makes it indispensable for developers. Whether for app development or addressing sophisticated software engineering challenges, Sonnet 4 balances performance and efficiency, offering an optimal solution for enterprises and individual developers seeking high-quality AI assistance.

Claude Pro is an advanced language model designed to handle complex tasks with a friendly and engaging demeanor. Built on a foundation of extensive, high-quality data, it excels at understanding context, identifying nuanced differences, and producing well-structured, coherent responses across a wide range of topics. Leveraging its strong reasoning skills and an enriched knowledge base, Claude Pro can create detailed reports, craft imaginative content, summarize lengthy documents, and assist with programming challenges. Its continually evolving algorithms enhance its ability to learn from feedback, ensuring that the information it provides remains accurate, reliable, and helpful. Whether serving professionals in search of specialized guidance or individuals who require quick and insightful answers, Claude Pro delivers a versatile and effective conversational experience, solidifying its position as a valuable resource for those seeking information or assistance. Ultimately, its adaptability and user-focused design make it an indispensable tool in a variety of scenarios.

Claude Haiku 3.5 is the next evolution in AI, combining speed, advanced reasoning, and powerful coding capabilities—all at a cost-effective price. Compared to its predecessor, Claude Haiku 3, this model delivers faster processing while surpassing the capabilities of Claude Opus 3, the previous largest model, on key intelligence benchmarks. Developers and businesses alike will benefit from its enhanced tool use, precise reasoning, and swift task execution. With text-only capabilities currently available, and plans for image input support in the future, Haiku 3.5 is the ideal solution for those looking for rapid, reliable, and efficient AI-powered support across various platforms.

Claude Opus 4.6 is an advanced AI language model developed by Anthropic, designed to handle complex reasoning, coding, and enterprise-level tasks with high accuracy. It introduces major improvements in planning, debugging, and code review, making it highly effective for software development workflows. The model is capable of sustaining long-running, agentic tasks and performing reliably across large and complex codebases. A key feature of Claude Opus 4.6 is its 1 million token context window in beta, enabling it to process vast amounts of information while maintaining coherence. It excels in knowledge work tasks such as financial analysis, research, and document creation. The model achieves state-of-the-art performance on multiple benchmarks, including coding and reasoning evaluations. Claude Opus 4.6 includes adaptive thinking, allowing it to dynamically adjust how deeply it reasons based on context. Developers can fine-tune performance using configurable effort levels that balance intelligence, speed, and cost. The model also supports context compaction, enabling longer workflows without exceeding limits. Integration with tools like Excel and PowerPoint enhances its usability for everyday business tasks. It maintains a strong safety profile with low rates of misaligned behavior and improved reliability. Overall, Claude Opus 4.6 is a powerful AI solution for advanced technical, analytical, and enterprise applications.

Claude Sonnet 4.6 is the latest evolution in Anthropic’s Sonnet model family, offering major advancements in coding, reasoning, computer interaction, and knowledge-intensive workflows. Designed as a full upgrade rather than an incremental update, it improves consistency, instruction following, and multi-step task completion across a broad range of professional applications. The model introduces a 1 million token context window in beta, enabling users to analyze entire codebases, long contracts, research archives, or complex planning documents in one cohesive session. Developers with early access reported a strong preference for Sonnet 4.6 over Sonnet 4.5 and even favored it over Opus 4.5 in many real-world coding tasks. Users highlighted its reduced overengineering tendencies, improved follow-through, and lower incidence of hallucinations during extended sessions. A major enhancement is its improved computer-use capability, allowing it to operate traditional software environments by interacting with graphical interfaces much like a human user. On benchmarks such as OSWorld, Sonnet models have shown steady gains in handling browser navigation, spreadsheets, and development tools. The model also demonstrates strategic reasoning improvements in long-horizon simulations, such as Vending-Bench Arena, where it optimizes early investments before pivoting toward profitability. On the Claude Developer Platform, Sonnet 4.6 supports adaptive thinking, extended thinking, and context compaction to maximize usable context length. API enhancements now include automated search filtering, code execution, memory, and advanced tool use capabilities for higher-quality outputs. Pricing remains consistent with Sonnet 4.5, making Opus-level performance more accessible to a broader user base. Available across Claude.ai, Cowork, Claude Code, the API, and major cloud platforms, Sonnet 4.6 becomes the new default model for Free and Pro users.