Anthropic launches Claude Sonnet 5.5: benchmarks, pricing and updates

Anthropic released Claude Sonnet 5.5 on September 28. In the company’s tests, it generates text more than 30% faster and can reduce cost per task by up to 30% compared with Sonnet 5.

The cover image is from Anthropic. See the original announcement and Anthropic’s post on X.

Sonnet 5.5 benchmarks vs. Sonnet 5 and Opus 5.5

Select an evaluation to compare the published results. Each chart retains its scale and unit: Elo for professional work; percentages for the other tests.

For a marketing team, each test answers a different question: Chartography measures chart interpretation; CursorBench evaluates code changes. We can use them to choose which tasks to try with the model. Campaign copy quality needs its own evaluation.

How much does Claude Sonnet 5.5 cost?

Official API pricing is US$2 per million input tokens, US$10 per million output tokens, and US$0.20 per million cache-read tokens. Per-token prices are unchanged from Sonnet 5. The reported savings come from using fewer tokens to finish the work. A Claude subscription is billed separately.

At those rates, a call with 10,000 input tokens and 2,000 output tokens costs US$0.04, excluding caching and tool charges. This is a calculated example: a report requiring several calls will have different usage.

How to access the Sonnet 5.5 API

The model ID is claude-sonnet-5-5. The model documentation lists access through the Claude Platform, AWS, Google Cloud and Microsoft Foundry, along with a one-million-token context window. For an existing integration, consult the migration guide before switching models.

What to try with Sonnet 5.5 in marketing

We suggest starting with deliverables the team can assess using its own materials:

1. Analyze posts: compare interactions on carousels from the same account and period, with the values used.
2. Prepare a draft: supply a brief and request copy for each slide, checking whether it preserves product facts.
3. Fix a landing page: specify a concrete problem and verify the change in a mobile preview before publishing.

With HeyMark connected to Claude, you can ask the assistant for your accounts’ posts and metrics to prepare that comparison. We have not yet tested Sonnet 5.5 with HeyMark; these are the use cases we propose evaluating.

Our guide to analyzing social media with real data shows how to request the figures and check the conclusions.