Question 1

What is Claude Opus 4.5?

Accepted Answer

Claude Opus 4.5 is a model from Anthropic, released on Nov 24, 2025. Claude Opus 4.5 is Anthropic’s frontier reasoning model optimized for complex software engineering, agentic workflows, and long-horizon computer use. $5 per million input tokens, $25 per million output tokens. 200,000 token context window, maximum output of 64,000 tokens. Higher uptime with 4 providers. Includes independent benchmarks from Artificial Analysis.

Question 2

How much does Claude Opus 4.5 cost?

Accepted Answer

On the Respan gateway, input starts at $5.00 per 1M tokens on every provider, and output starts at $25.00 per 1M tokens on every provider, after gateway discounts.

Question 3

Which providers serve Claude Opus 4.5 on Respan?

Accepted Answer

5 providers serve Claude Opus 4.5: Anthropic, OpenRouter, Perplexity, and Google Vertex AI. Perplexity and Google Vertex AI require your own provider API key (BYOK).

Question 4

What is Claude Opus 4.5's context window?

Accepted Answer

Claude Opus 4.5 accepts up to 200K tokens of context on its largest provider route.

Question 5

How do I use Claude Opus 4.5 with the Respan gateway?

Accepted Answer

Point any OpenAI-compatible SDK at https://api.respan.ai/api/ with your Respan API key and set the model to "anthropic/claude-opus-4-5". To set it up with a coding agent, copy the agent setup prompt at the top of this page.

Question 6

How fast is Claude Opus 4.5?

Accepted Answer

Over the last 30 days of requests through the Respan gateway, the fastest provider was Anthropic at 273 tokens per second, and the lowest response latency was 1.2 seconds on Anthropic. Speed varies with request size and provider.

Question 7

Where does Claude Opus 4.5 rank on the Respan Index?

Accepted Answer

Claude Opus 4.5 scores 37.5 out of 100 on the Respan Index v1.1, ranking #52 of 138 models. By category: Coding 19.3, Agents 53.7, Reasoning 27.2, Knowledge & language 45.3, and Human preference 52.6. The Respan Index combines independent and lab-reported benchmark results into one score, using benchmark data collected by llmmetric.com.

Question 8

How does Claude Opus 4.5 score on benchmarks?

Accepted Answer

Claude Opus 4.5 has 39 published benchmark scores, including SWE-bench Verified 80.9%, τ2-bench (Telecom) 98.2%, and GPQA Diamond 87%. Each score links to where it was published; the data is collected by llmmetric.com.

Provider	Context	Input	Output
Anthropic`anthropic/claude-opus-4-5`	200K	$5.00/M	$25.00/M
Anthropic`anthropic/claude-opus-4-5-20251101`	200K	$5.00/M	$25.00/M
OpenRouter`openrouter/anthropic/claude-opus-4.5`	200K	$5.00/M	$25.00/M
PerplexityBYOK only`perplexity/anthropic/claude-opus-4-5`	200K	$5.00/M	$25.00/M
Google Vertex AIBYOK only`vertex_ai/claude-opus-4-5@20251101`	200K	$5.00/M	$25.00/M

Claude Opus 4.5

Providers

Certified where it counts.

Pricing

Cost by volume

Throughput and latency

Output speed

Time to first token

Response latency

Benchmarks

Respan Indexv1.1

Coding6

Apps

Claude Opus 4.5 FAQ

Works with your entire stack

Built for AI agents.
Break less.
Ship more.

Agents11

Reasoning9

Math4

Knowledge4

Multimodal2

Arena2

Other1