# Claude Sonnet 5.5: API price, context window and how to connect

Claude Sonnet 5.5 by Anthropic: $2 per million input tokens, $10 per million output tokens, a 1M-token window. What it is good for, what to compare it with and how to connect it in SKILLOK.

## In short

A Sonnet-class model for well-scoped everyday work, a direct upgrade of Claude Sonnet 5. Strong at building features, fixing bugs and producing work materials.

## Specifications

| | |
|---|---|
| Provider | [Anthropic](https://skillok.org/docs/en/ai-models/providers/anthropic) |
| Released | 2026-09-28 |
| Context window | 1M tokens |
| Accepts | text, images, files |
| Answers with | text |
| Reasoning mode | yes |
| Tool calling | yes |
| Open weights | no |
| Identifier | `anthropic/claude-sonnet-5.5` |

## Price

| Per 1M tokens | In dollars |
|---|---|
| Input (question, context) | $2 |
| Output (answer) | $10 |

For reference: a conversation of 20 questions of ~500 tokens and answers of ~800 tokens costs about **$0.18**. Models in reasoning mode spend more tokens on an answer than the text shows: the reasoning is paid for too.

## What it is good for

* A new feature or a bug fix
* Texts and documents for work
* The main everyday model

## Similar models

Catalog models with the same kind of output, closest in the price of a typical request.

| Model | Input | Output | Window | Price |
|---|---|---|---|---|
| [GPT-6.1 Sol](https://skillok.org/docs/en/ai-models/models/gpt-6-1-sol) | $2 | $10 | 1.05M | about the same |
| [GPT-6.1 Sol Pro](https://skillok.org/docs/en/ai-models/models/gpt-6-1-sol-pro) | $2 | $10 | 1.05M | about the same |
| [Gemini 4 Argon](https://skillok.org/docs/en/ai-models/models/gemini-4-argon) | $2 | $10 | 1.05M | about the same |
| [GLM 5.3 Prime](https://skillok.org/docs/en/ai-models/models/glm-5-3-prime) | $2.8 | $8.8 | 1M | about the same |
| [Kimi K3](https://skillok.org/docs/en/ai-models/models/kimi-k3) | $0.239 | $11.936 | 1.05M | about the same |

## Other Anthropic models

* [Claude Opus 5.5](https://skillok.org/docs/en/ai-models/models/claude-opus-5-5)
* [Claude Haiku 5.5](https://skillok.org/docs/en/ai-models/models/claude-haiku-5-5)
* [Claude Fable 5.1](https://skillok.org/docs/en/ai-models/models/claude-fable-5-1)
* [Claude Opus 5](https://skillok.org/docs/en/ai-models/models/claude-opus-5)

## How to connect in SKILLOK

Claude Sonnet 5.5 works through OpenRouter: add an OpenRouter key in **Settings → AI** and pick the `anthropic/claude-sonnet-5.5` model. It then becomes available in Space AI, in tasks and to the repository agent. In detail — [Connecting a model in SKILLOK](https://skillok.org/docs/en/ai-models/connecting-in-skillok).

## Where the data comes from

Prices, the context window and capabilities come from the public OpenRouter catalog as of 2026-10-19. A provider may change the price — the exact figure is always on the model's OpenRouter page.

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https://skillok.org/docs/en/ai-models/models/claude-sonnet-5-5