Anthropic: Claude Sonnet 4.5
Analysis Summary
Claude Sonnet 4.5 is Anthropic's capable general-purpose model for reasoning, coding, and agentic workflows. It combines strong coding and agentic results with a 1M context window, vision, file input, tool use, and function calling. Instruction following and long-context performance support dependable work across detailed briefs, large codebases, and complex client documentation.
This is a strong fit for software engineering, autonomous task assistance, long-document analysis, SEO strategy, and customer-facing content where consistency matters. The broad modality and tool support reduce the need to split workflows across several specialised models. Its main limitation is price, particularly for output, so routing routine or high-volume traffic elsewhere is sensible. Adopt Sonnet 4.5 for high-value production tasks that need depth, context retention, and reliable multi-step execution.
Assessed August 9, 2026
Editorial notes
Claude Sonnet 4.5 combines strong coding and agentic performance with a 1M context, vision, file input, tool use, and precise instruction following. Premium pricing makes it better suited to high-value work than bulk generation.
Rankings consider pricing, capabilities, benchmarks, and real-world applicability and are refreshed as new models launch. Feedback?
DFO Verdict
Claude Sonnet 4.5 combines strong coding and agentic performance with a 1M context, vision, file input, tool use, and precise instruction following. Premium pricing makes it better suited to high-value work than bulk generation.
Benchmark scores
Magenta = intelligence · Ink = technical/agentic · Cyan = content & long-context · Grey = community benchmarks. Data: Artificial Analysis, Hugging Face.
36.4 Intelligence Index·52.1 Coding Index·56.8 Agentic Index·88 Math Index
How Anthropic: Claude Sonnet 4.5 compares
Anthropic: Claude Sonnet 4.5 ranks #81 of 420 AI models we track for overall intelligence, #56 of 193 for coding, #9 of 175 for agentic tasks. Its 1M-token context window is larger than 86% of the models we list. At $3.00 per million input tokens it is cheaper than 11% of comparable models.
Dark bar = input · light bar = output, scaled to the priciest peer.
1M tokens ≈ 8 full-length novels or ~2,500 pages of business documents in a single request.
Strongest on content. The pulled-in intelligence corner is the trade-off, and if the shape matters more than the price, this is your model.
Compare shapes side-by-side →Pricing
| Token Type | Cost per 1M tokens | Cost per 1K tokens |
|---|---|---|
| Input | $3.00 | $0.003000 |
| Output | $15.00 | $0.015000 |
What would Anthropic: Claude Sonnet 4.5 cost your business?
Pick the job that looks most like yours, then fine-tune with the sliders. Estimates update live.
A website chatbot handling around 100 customer conversations a day, a few short messages each.
Full calculator with 688 models → Price Calculator
These numbers get smaller with the right architecture.
We route routine calls to cheap models and save Anthropic: Claude Sonnet 4.5 for the hard ones. Most clients cut their estimate by 60-80%.
Talk to our teamAbout Anthropic: Claude Sonnet 4.5
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..
Frequently asked questions about Anthropic: Claude Sonnet 4.5
How much does Anthropic: Claude Sonnet 4.5 cost?
Anthropic: Claude Sonnet 4.5 costs $3.00 per million input tokens and $15.00 per million output tokens.
What is the context window of Anthropic: Claude Sonnet 4.5?
Anthropic: Claude Sonnet 4.5 has a context window of 1,000,000 tokens (1M).
Is Anthropic: Claude Sonnet 4.5 good for coding?
On our coding benchmark index, Anthropic: Claude Sonnet 4.5 ranks #56 of 193 models, placing it in the broader range of the field for code generation and debugging.
What can Anthropic: Claude Sonnet 4.5 do?
Anthropic: Claude Sonnet 4.5 supports image/vision input, tool use, and function calling.
Who created Anthropic: Claude Sonnet 4.5?
Anthropic: Claude Sonnet 4.5 is developed by Anthropic and was released on September 29, 2025.
