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About Claude Opus 5 (Fast)
Fast-mode variant of [Opus 5](/anthropic/claude-opus-5) - identical capabilities with higher output speed at 2x pricing relative to regular Opus 5. Learn more in Anthropic's docs: https://platform.claude.com/docs/en/build-with-claude/fast-mode
Technical Specifications
- Model ID
- anthropic-claude-opus-5-fast
- Category
- LLM Models
- Task
- Text Generation
- Price
- $30 per million tokens
- Added
- July 24, 2026
Key Features
- Chat completion and multi-turn conversation API
- Streaming response with token-by-token output
- Function calling and tool use support
- System prompts and role-based messaging
- JSON mode and structured output
Quick Start
Integrate Claude Opus 5 (Fast) into your application with a single API call. Get your API key from the pricing page to get started.
import requestsimport jsonurl = "https://modelslab.com/api/v7/llm/chat/completions"headers = {"Content-Type": "application/json"}data = {"model_id": "anthropic-claude-opus-5-fast","messages": [{"role": "user","content": "Hello!"}],"max_tokens": 1000,"key": "YOUR_API_KEY"}try:response = requests.post(url, headers=headers, json=data)response.raise_for_status() # Raises an HTTPError for bad responses (4XX or 5XX)result = response.json()print("API Response:")print(json.dumps(result, indent=2))except requests.exceptions.HTTPError as http_err:print(f"HTTP error occurred: {http_err} - {response.text}")except Exception as err:print(f"Other error occurred: {err}")
Pricing
Claude Opus 5 (Fast) API costs $30.000000 per million tokens. Pay only for what you use with no minimum commitments. View pricing plans
Use Cases
- AI chatbots and virtual assistants
- Code generation and developer tools
- Content writing and copywriting automation
- Data analysis, summarization, and extraction
Claude Opus 5 (Fast) FAQ
Fast-mode variant of [Opus 5](/anthropic/claude-opus-5) - identical capabilities with higher output speed at 2x pricing relative to regular Opus 5. Learn more in Anthropic's docs: https://platform.claude.com/docs/en/build-with-claude/fast-mode
You can integrate Claude Opus 5 (Fast) into your application with a single API call. Sign up on ModelsLab to get your API key, then use the model ID "anthropic-claude-opus-5-fast" in your API requests. We provide SDKs for Python, JavaScript, and cURL examples in the API documentation.
Claude Opus 5 (Fast) costs $30.000000 per million tokens. ModelsLab plans start at $21/month (Basic), and the $149/month Open Source plan includes unlimited generation on open-source models.
The model ID for Claude Opus 5 (Fast) is "anthropic-claude-opus-5-fast". Use this ID in your API requests to specify this model.
Yes. ModelsLab is subscription-based with no free tier — plans start at $21/month (Basic, 3,250 API calls). The $149/month Open Source Unlimited plan includes unlimited generation across open-source models; premium third-party models are billed per call from your wallet.