Claude Opus 4.5 API

anthropic/claude-opus-4.5
Claude 4.5 Opus is a breakthrough AI model offering unmatched intelligence, multi-step reasoning, and efficiency.
Context
200K tokens
Input
$6.877 / 1M tokens
Output
$32.5 / 1M tokens

How to use Claude Opus 4.5 API

Install any OpenAI-compatible SDK, point it at api.aimlapi.com/v1, and set the model to anthropic/claude-opus-4.5.
import requests

r = requests.post(
    "https://api.aimlapi.com/v1/chat/completions",
    headers={"Authorization": "Bearer " + AIMLAPI_KEY},
    json={
      "model": "anthropic/claude-opus-4.5",
      "messages": [
        {
          "role": "user",
          "content": "Hello!"
        }
      ]
    },
)
print(r.json())
const r = await fetch("https://api.aimlapi.com/v1/chat/completions", {
  method: "POST",
  headers: {
    Authorization: `Bearer ${process.env.AIMLAPI_KEY}`,
    "Content-Type": "application/json",
  },
  body: JSON.stringify({
    "model": "anthropic/claude-opus-4.5",
    "messages": [
      {
        "role": "user",
        "content": "Hello!"
      }
    ]
  }),
});
console.log(await r.json());
curl -X POST https://api.aimlapi.com/v1/chat/completions \
  -H "Authorization: Bearer $AIMLAPI_KEY" \
  -H "Content-Type: application/json" \
  -d '{"model":"anthropic/claude-opus-4.5","messages":[{"role":"user","content":"Hello!"}]}'

OpenAI-compatible — swap the base URL and it works with your existing SDK.

Claude Opus 4.5 API Pricing

TypePrice
Input
$6.877 / 1M tokens
Output
$32.5 / 1M tokens
Cached input
$0.6877 / 1M tokens

Claude Opus 4.5 Benchmarks

BenchmarkScoreWhat it measuresSourceRetrieved
GPQA Diamond
87%
Google-proof graduate science questions (hardest subset)SourceJuly 8, 2026
OSWorld
66.3%
Computer-use across real desktop applicationsSourceJuly 8, 2026
Terminal-Bench
59.3%
Autonomous shell/terminal task completionSourceJuly 8, 2026
SWE-bench Verified
80.9%
Resolving verified real GitHub issuesSourceJuly 8, 2026
Intelligence
29.1
Composite score across standardised reasoning, knowledge and problem-solving evaluations, measured independently by Artificial AnalysisSourceSeptember 12, 2026
Math
91.3
Composite score across standardised mathematics evaluations, measured independently by Artificial AnalysisSourceSeptember 12, 2026

Claude Opus 4.5 vs other models

ModelInputOutputContextBest for
$6.877 / 1M tokens
$32.5 / 1M tokens
200K tokens
Chat + assistants
$6.5 / 1M tokens
$39 / 1M tokens
1.05M tokens
Reasoning + agents
$2.6 / 1M tokens
$13 / 1M tokens
1M tokens
Balanced coding + agents
$3.9 / 1M tokens
$19.5 / 1M tokens
1M tokens
Long-context, multimodal & agentic workflows
$0.65 / 1M tokens
$3.9 / 1M tokens
1.05M tokens
Reasoning + agents

Frequently asked questions

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