September 29, 2025 - 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 3.5 Sonnet is now available for free on Claude.ai and the Claude iOS app, while Claude Pro and Team plan subscribers can access it with significantly higher rate limits. It is also available via the Anthropic API, Amazon Bedrock, and Google Cloud’s Vertex AI.

4 days ago - Anthropic Claude: Anthropic’s Claude (founded by ex-OpenAI researchers) offers Claude 3.x (“Haiku”, “Sonnet”, “Opus” versions) and even a Claude 4 series. It has a free tier and a $20/mo Pro plan for individuals ([8]), plus $100/$200 power-user plans ([7]). Critically, Anthropic publishes per-token API prices for each model.

Talk with Claude, an AI assistant from Anthropic

7 hours ago - Claude’s API offers multiple model families, each with different performance and cost profiles. Anthropic categorizes its models as “Haiku” (fastest, smallest), “Sonnet” (balanced), and “Opus” (most capable, most expensive).

September 29, 2025 - Claude Sonnet 4.5 is Anthropic’s most advanced Sonnet model to date, optimized for real-world agents and coding workflows. Run Claude Sonnet 4.5 with API

👉 Claude-3-Sonnet API balances speed with performance, excels in multilingual tasks, and integrates seamlessly with cloud platforms. Important: Claude 3 Sonnet will be retired on July 21st, 2025.

Powered by Anthropic: claude-sonnet-4-5-20250929. Learn more ... import openai client = openai.OpenAI( api_key = "YOUR_POE_API_KEY", # or os.getenv("POE_API_KEY") base_url = "https://api.poe.com/v1", ) chat = client.chat.completions.create( model = "claude-sonnet-4.5", messages = [{ "role": "user", "content": "Create an HTML5 page where I can play pong against the computer" }] ) print(chat.choices[0].message.content)

3 weeks ago - Gemini 3 Pro's million-token context window enables processing entire codebases, books, or extensive document collections in a single prompt. Claude 4.5 Sonnet offers a 1M beta via API header (context-1m-2025-08-07), while GPT 5.1's "compaction" ...

“We're seeing state-of-the-art coding performance from Claude Sonnet 4.5, with significant improvements on longer horizon tasks.

Build with the Claude API

3 weeks ago - Claude app conversations get automatically summarized past a maximum length, thus early details will be forgotten but there is no longer any maximum length for chats. Opus-specific caps on usage have been removed. Opus is now $5/$25 per million input and output tokens, a 66% price cut. It is now only modestly more than Sonnet, and given it is also more token efficient there are few tasks where you would use any model other than Opus 4.5.

1 month ago - Sonnet 4.5 works well for standard chat, mid-level coding, or fast drafting. Haiku 4.5 is often ideal for extremely high-volume, low-latency use cases. Multimodal or video-heavy tasks will still require specialized models outside the Claude lineup.

February 25, 2025 - Constructs a prompt for Claude 3.7 Sonnet: The prompt instructs the model to: Summarize each paper. Identify key drawbacks. Find interconnections between papers. Generate a novel research idea combining techniques from different papers. Initializes streaming API request: Once the prompt is set, next we use client.messages.stream() to send the request to Claude 3.7 Sonnet.

1 month ago - Claude Sonnet 4.5 is designed as the sweet spot between speed, cost and intelligence, and is marketed as: ... Below is an approximate comparison for standard API usage at ≤ 200k tokens per prompt.

July 8, 2024 - The Claude API lets you integrate Claude's AI models into your apps. You can send prompts to Anthropic (the company behind Claude) and get the outputs delivered to you wherever you need them: you can save them to your database, display them ...

1 month ago - Claude Opus 4.5, Sonnet 4.5, and Haiku 4.5 are available now via the Claude API, on all major cloud platforms, and through Anthropic's consumer applications.

1 month ago - For API-heavy teams, blend plans: Use Pro for ideation, API for production. This hybrid minimizes Claude Opus 4.5 Pricing exposure. Legacy Opus variants underscore the value shift. Opus 4.1 charged $15 input/$75 output per million tokens—five times Opus 4.5's input rate. Sonnet 4.5, at $3/$15 (≤200K tokens), serves mid-tier needs but lags in complex reasoning; Haiku 4.5 ($1/$5) prioritizes speed over depth.