Claude Opus 4.5 API
Pay 65% less.
On input and output tokens, compared with official prices.
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claude-opus-4.5Claude Opus 4.5
overview.
Claude Opus 4.5 is an earlier Anthropic Opus release with a smaller published context window than Opus 4.6 and the later entries. Its evaluation uses the Reasoning label rather than the Max labels shown for those releases. Use this entry’s own specifications and model ID when comparing an existing integration with a newer Opus model.
Published model specifications
OPTIONAL / CONNECTIONAPI request example
Set the model ID and base URL in your OpenAI-compatible client.
https://aelder.dev/v1Compare Claude model prices or follow the Python and JavaScript SDK setup.
import os
from openai import OpenAI
client = OpenAI(
api_key=os.environ["AELDER_API_KEY"],
base_url="https://aelder.dev/v1",
)
response = client.chat.completions.create(
model="claude-opus-4.5",
messages=[{"role": "user", "content": "Hello!"}],
)
print(response.choices[0].message.content)import OpenAI from "openai";
const client = new OpenAI({
apiKey: process.env.AELDER_API_KEY,
baseURL: "https://aelder.dev/v1",
});
const response = await client.chat.completions.create({
model: "claude-opus-4.5",
messages: [{ role: "user", content: "Hello!" }],
});
console.log(response.choices[0].message.content);curl https://aelder.dev/v1/chat/completions \
-H "Authorization: Bearer $AELDER_API_KEY" \
-H "Content-Type: application/json" \
-d '{
"model": "claude-opus-4.5",
"messages": [{"role": "user", "content": "Hello!"}]
}'claude-opus-4.5Chat CompletionsClaude Opus 4.5 benchmarks.
Compare models in the AELDER catalog on the same external measure. The Artificial Analysis Intelligence Index combines evaluations of model capability. Higher is better; the score is not a percentage.
Artificial Analysis Intelligence Index
VERSION 4.3.2 · INDEX POINTS · HIGHER IS BETTER| Model | Source configuration | Index |
|---|---|---|
| Claude Opus 5.5 | Claude Opus 5.5 (Max, Default Fallback) | 58 |
| Claude Sonnet 5.5 | Claude Sonnet 5.5 (Max, Default Fallback) | 56 |
| Claude Fable 5.1 | Claude Fable 5.1 (Max, Default Fallback) | 53 |
| GPT 6 Astra | GPT-6 Astra (Max) | 53 |
| GPT 6.1 Sol | GPT-6.1 Sol (Max) | 52 |
| Claude Opus 5 | Claude Opus 5 (Max) | 51 |
| Claude Fable 5 | Claude Fable 5 (Max, Opus 4.8 Fallback) | 50 |
| GPT 6 Sol | GPT-6 Sol (Max) | 48 |
| GPT 5.6 Sol | GPT-5.6 Sol (Max) | 47 |
| DeepSeek V4.1 Flash | DeepSeek V4.1 Flash 1017 (Max) | 45 |
| GLM 5.3 | GLM-5.3 (Max) | 45 |
| Qwen3.8 Max 0902 | Qwen3.8 Max (0902) | 45 |
| Grok 4.6 | Grok 4.6 (Xhigh) | 44 |
| Kimi K3 | Kimi K3 (Max) | 44 |
| Claude Haiku 5.5 | Claude Haiku 5.5 (Max) | 43 |
| Claude Opus 4.8 | Claude Opus 4.8 (Max) | 42 |
| GLM 5.3 Flash | GLM-5.3-Flash | 42 |
| GPT 5.6 Terra | GPT-5.6 Terra (Max) | 42 |
| Claude Opus 4.7 (1M) | Claude Opus 4.7 (Max) | 41* |
| Gemini 3.8 Flash | Gemini 3.8 Flash (High) | 41 |
| Qwen3.8 2.4T-A95B | Qwen3.8 2.4T A95B | 40 |
| Qwen3.8 Max | Qwen3.8 Max | 40 |
| Claude Sonnet 5 | Claude Sonnet 5 (Max) | 38 |
| GPT 6 Luna | GPT-6 Luna (Max) | 38 |
| GPT 5.6 Luna | GPT-5.6 Luna (Max) | 37 |
| DeepSeek V4 Pro | DeepSeek V4 Pro 0813 (Max) | 36 |
| GLM 5.2 | GLM-5.2 (Max) | 34 |
| Qwen3.8 27B | Qwen3.8 27B (Xhigh) | 34 |
| GPT 5.3 Codex | GPT-5.3 Codex (Xhigh) | 33* |
| Claude Opus 4.6 | Claude Opus 4.6 (Max) | 32* |
| Claude Sonnet 4.6 | Claude Sonnet 4.6 (Max) | 30 |
| Gemini 3.1 Pro | Gemini 3.1 Pro Preview | 30 |
| Claude Opus 4.5Current | Claude Opus 4.5 (Reasoning) | 29* |
| MiniMax M3 | MiniMax-M3 | 29 |
| Kimi K2.6 | Kimi K2.6 (Reasoning) | 27 |
| GLM 5.1 | GLM-5.1 (Reasoning) | 26 |
| Kimi K2.7 Code | Kimi K2.7 Code | 26 |
| Hy3 | Hy3 | 25 |
| DeepSeek V4 Flash | DeepSeek V4 Flash 0420 (Max) · April 2026 reference | 24 |
| Kimi K2.5 | Kimi K2.5 (Reasoning) | 23* |
| MiniMax M2.7 | MiniMax-M2.7 | 23 |
DeepSeek V4 Flash uses the April 0420 release reference, labelled in the chart and table. External results refer to the labelled source configurations, which may differ from AELDER’s configuration. They do not measure AELDER API speed or uptime. Source score markers (*) are preserved.
Why are 4 catalog models missing a score?
41 of 45 catalog models have a source reference on this index version. A missing result is not a zero score. These models remain in the catalog.
Claude Opus 4.5 alternatives.
Claude Opus 4.5
questions, answered.
Does the AELDER model ID need the publisher’s dated suffix?
claude-opus-4.5, exactly as shown in the API example on this page. Model identifiers belong to the API service you call; do not replace this ID with a dated publisher ID unless the service documents it.Your next idea,
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