Model · Anthropic

Claude Opus 5.5

Claude Opus 5.5 is served by Anthropic through OpenRouter. It provides 1M tokens of context and supports text, vision, files inputs.

Snapshot 2026-10-10 anthropic/claude-opus-5.5

Context window

1M tokens

Input / 1M tokens

$4.00

Output / 1M tokens

$20.00

Key facts

Provider	Anthropic
OpenRouter ID	`anthropic/claude-opus-5.5`
Modalities	Text, Vision, Files
Best for	Overall, Coding, Agents

Source openrouter.ai/api/v1/models Verified 2026-10-10 Drift-checked daily 06:00 CST

Best-fit workloads

Best overall

Strong reasoning, tooling and production reliability.

Best for coding

Good code quality, debugging and technical explanation.

Best for agents

Tool use, structured output and multi-step reasoning.

Cost estimates

These examples use the 2026-10-10 input and output prices. Cache discounts, provider surcharges and tool fees are excluded.

Workload	Input	Output	Estimated cost
Quick test	20,000	5,000	$0.180
Product chat month	500,000	125,000	$4.50
Document batch	5,000,000	1,000,000	$40.00

Strengths

✓ Anthropic's flagship tier: multi-step changes across large codebases and long-horizon agent work
✓ 1M-token window with a 128K output ceiling, the same shape as the rest of the Claude 5.x line
✓ Cached reads at a twentieth of the input price, which is what a long agent session actually spends

Limitations

! $4 in / $20 out per million makes it the most expensive Claude row here — worth it only when a wrong answer costs more than the tokens
! Text output only; images and files go in and text comes out
! Successor positioning to Opus 5 is the vendor's, not a measurement we ran

OpenRouter API quickstart

Run these examples from your server or edge function. Keep the OpenRouter API key private and do not expose it in browser code.

cURL

curl https://openrouter.ai/api/v1/chat/completions \
  -H "Authorization: Bearer $OPENROUTER_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "anthropic/claude-opus-5.5",
    "messages": [{ "role": "user", "content": "Summarize this document in five bullet points." }],
    "max_tokens": 500
  }'

JavaScript / TypeScript

const response = await fetch("https://openrouter.ai/api/v1/chat/completions", {
  method: "POST",
  headers: {
    Authorization: `Bearer ${process.env.OPENROUTER_API_KEY}`,
    "Content-Type": "application/json",
  },
  body: JSON.stringify({
    model: "anthropic/claude-opus-5.5",
    messages: [{ role: "user", content: "Summarize this document in five bullet points." }],
    max_tokens: 500,
  }),
});

const data = await response.json();
console.log(data.choices[0].message.content);

How to evaluate Claude Opus 5.5

Run five real tasks from your product, not generic demo prompts.
Record token usage, latency and output quality.
Estimate cost using your real input/output mix.
Compare it against one model with a similar price and one stronger model.

Compare models View on OpenRouter ↗

Claude Opus 5.5 FAQ

What is Claude Opus 5.5?

Claude Opus 5.5 is a Anthropic model available through OpenRouter. It supports text, vision, files inputs and is suited for overall, coding, agents workloads.

How much does Claude Opus 5.5 cost on OpenRouter?

The 2026-10-10 snapshot lists $4.00 per 1M input tokens and $20.00 per 1M output tokens. Verify current pricing on OpenRouter before production.

How large is Claude Opus 5.5's context window?

Claude Opus 5.5 offers 1M tokens of context in the current snapshot. Provider-specific limits and surcharges may apply.

Head-to-head comparisons

Claude Opus 5.5 vs Claude Sonnet 5.5

Inside one family the choice is unusually clean: you are buying the top tier of the same line, and the cliff between them is the point of the lineup. Route the hard 10% of tasks to Opus and the other 90% to Sonnet, and you cut the bill while keeping the ceiling — providing your routing is better than a coin flip.

Grok 4.7 vs Claude Opus 5.5

The interesting number is not the price, it is the two ceilings: 450K output at $6 per million is a shape of capability that Opus at $20 does not sell. If your work is long-running engineering loops where the model must produce and check a lot of text, Grok's economics are different in kind; if the job is a large codebase in one window, Opus buys the window.

Pricing and context data are based on a 2026-10-10 snapshot. Provider limits can change; always verify on OpenRouter before production.