The model also shows improved capabilities on a broad range of evaluations including reasoning and math: Claude Sonnet 4.5 is our most powerful model to date.

When we release new model snapshots, we migrate aliases to point to the newest version of a model, typically within a week of the new release. While aliases are useful for experimentation, we recommend using specific model versions (e.g., claude-sonnet-4-5-20250929) in production applications to ensure consistent behavior.

Pricing for Sonnet 4.5 starts at $3 per million input tokens and $15 per million output tokens, with up to 90% cost savings with prompt caching and 50% cost savings with batch processing. To learn more, check out our pricing page. To get started, simply use claude-sonnet-4-5 via the Claude API.

Claude Sonnet 4.5 is Anthropic’s most advanced Sonnet model to date, optimized for real-world agents and coding workflows. It delivers state-of-the-art performance on coding benchmarks such as SWE-bench Verified, with improvements across system ...

September 29, 2025 - This new model builds upon Claude 4’s foundation to achieve state-of-the-art performance in coding and complex agentic applications. Claude Sonnet 4.5 demonstrates advancements in agent capabilities, with enhanced performance in tool handling, ...

Claude Sonnet 4.5 is our best model for building complex agents that can work independently for extended periods. It advances the frontier in coding capabilities, achieves state-of-the-art performance in computer use, and excels at powering ...

2 days ago - GitHub placed Sonnet 4.5 in public preview for Copilot Chat and enabled it for the Copilot coding agent, soon after release. Anthropic stated that Sonnet 4.5 is its "most aligned frontier model" to date.

Claude Sonnet 4.5 represents a major leap forward in AI capability and alignment. It is the most advanced model released by Anthropic to date, distinguished by dramatic improvements in reasoning, mathematics, and real-world coding. Supports 1m tokens of context.

Claude Opus 4.5: Our most intelligent model combining maximum capability with practical performance. Features a more accessible price point than previous Opus models. Available with a 200k token context window.

Anthropic's mid-sized model for powering real-world agents, with capabilities in coding, computer use, cybersecurity, and working with office files like spreadsheets.

October 7, 2025 - Sonnet 4.5 is already live in Anthropic’s API and on the Claude chatbot (as part of the Max plan). You can invoke it via the API model name claude-sonnet-4-5 at the same token pricing as before ([2]). Claude Code 2.0 is rolling out with these ...

import requests import json # for getting a structured output with indentation response = requests.post( "https://api.aimlapi.com/v1/chat/completions", headers={ # Insert your AIML API Key instead of <YOUR_AIMLAPI_KEY>: "Authorization":"Bearer <YOUR_AIMLAPI_KEY>", "Content-Type":"application/json" }, json={ "model":"anthropic/claude-sonnet-4.5", "messages":[ { "role":"user", "content":"Hello" # insert your prompt here, instead of Hello } ] } ) data = response.json() print(json.dumps(data, indent=2, ensure_ascii=False))

Claude Sonnet 4.5 is Anthropic's most capable model to date for building real-world agents and handling complex, long-horizon tasks, balancing the right speed and cost for high-volume use cases.

... Claude Sonnet 4.5 is Anthropic's latest Sonnet-class model for powering real-world agents, with industry leading capabilities around coding, computer use, cybersecurity, and working with office files like spreadsheets.

September 29, 2025 - We’re thrilled to announce the rollout of Claude Sonnet 4.5, Anthropic’s latest and most capable coding model. Starting today, Sonnet 4.5 is the default model for Augment Code, and will appear alongside GPT-5 in the model picker.

Google Cloud Console has failed to load JavaScript sources from www.gstatic.com. Possible reasons are:www.gstatic.com or its IP addresses are blocked by your network administratorGoogle has temporarily blocked your account or network due to excessive automated requestsPlease contact your network ...

Claude 4.5 Sonnet is a large language model (LLM) in Anthropic’s Claude family that supports conversational chat, tool calling, and enhanced reasoning for complex tasks with extended thinking.