Claude Sonnet 5.5

Claude Sonnet 5.5 is a fast Claude model from Anthropic for everyday coding, agents, and knowledge work. It is the latest release in the claude-sonnet line, succeeding Claude Sonnet 5, which was released on 2026-06-29 with the same 1,000,000-token context window. The model has a context window of 1,000,000 tokens and a maximum output of 128,000 tokens. Pricing starts at $2.00 per million input tokens and $10.00 per million output tokens, with cached input at $0.20 per million tokens. Weights are not open. It supports reasoning mode, tool calling, and accepts image, PDF, and text inputs, returning text. Knowledge cutoff is 2026-06. It is served by 13 hosts.

Against Claude Sonnet 5: input $1.44 to $2.00, output $7.20 to $10.00.

Range across the hosts that serve it: up to $2.50 per 1M input tokens.

• ·1,000,000-token context window
• ·128,000-token maximum output
• ·Supports reasoning mode and tool calling
• ·Accepts image, PDF, and text inputs
• ·Cached input at $0.20 per million tokens

• Reach for it for everyday coding tasks
• Reach for it for building AI agents
• Reach for it for knowledge work with long documents
• Reach for it for tasks needing image or PDF understanding

13 hosts serve this model at the price above · the maker's documentation

• 8GPT-6.1 Sol (Max) Enters Agent Arena at Rank 5, Approaching Top Models at Lower Cost2026-10-03
• 8Artificial Analysis: Claude Sonnet 5.5, GPT-6.1 Sol and Gemini 4 Argon Top Coding Agent Index but Costs Vary2026-10-02
• 9Claude Sonnet 5.5 (High) Scores 1699 to Rank 4th in Code Arena: WebDev2026-09-30
• 8Anthropic's mid-tier Claude climbs the rankings2026-09-30
• 9Claude Sonnet 5.52026-09-29
• 9Sonnet 5.52026-09-29

6 signals of the archive mention this model, each scored against the published bar. This list is rebuilt from the archive at every build, so it cannot go stale.

The registry keeps the six most recent versions of a line. Older ones stay in the file and can be surfaced without a rebuild.

What is the context window and output limit?

The context window is 1,000,000 tokens and the maximum output is 128,000 tokens.

What does it cost per token?

Input costs from $2.00 per million tokens, output from $10.00 per million tokens, and cached input at $0.20 per million tokens.

Does it support image and PDF inputs?

Yes, it accepts image, PDF, and text inputs, and returns text output. It also supports reasoning mode and tool calling.