Claude Sonnet 5.5 now available in Model ML
5 MIN. READ
Claude Sonnet 5.5 is live in Model ML.
Ahead of its launch, Model ML worked closely with the Anthropic team to test it against the Model ML Composite, our proprietary benchmark for AI in financial services. Several findings stood out to our evaluations team:
Near-Opus quality at a fraction of the cost. Anthropic's latest model stays close to Opus 5.5 in four of our five categories and costs 56–78% less in all five. That puts it right on the cost–performance frontier for analytical finance, PowerPoint creation and multi-document work.
A standout slide builder for the cost. On PowerPoint creation, Sonnet 5.5 comes close to the top slide builders (Opus 5.5, GPT-6 Astra and Fable 5.1) at less than half the cost of any of them. It also beats GPT-5.6 Sol, GPT-6 Sol and Gemini 3.8 Flash on both quality and cost, and it comfortably outscores the best open model, DeepSeek 4.1 Flash, while costing less.
Among the leaders on multi-document work, at a mid-range cost. Sonnet 5.5 sits on the cost–performance frontier, just behind Opus 5.5 and Gemini 3.8 Flash, with GPT-6 Astra leading the category. It also comes in ahead of Fable 5.1 at a fraction of its cost.
On pure-play financial workflows, open models outperform Sonnet 5.5. DeepSeek 4.1 Flash and Kimi K3 both outscore Sonnet 5.5, with DeepSeek at a fraction of the price.
Try Claude Sonnet 5.5 in Model ML today.
