--- title: Claude Opus 5 (Fast) API | Text Generation | ModelsLab description: Build with Claude Opus 5 (Fast) API by Anthropic. Text generation, chat, code, and reasoning. Plans from $21/month. url: https://modelslab.com/models/anthropic/anthropic-claude-opus-5-fast.md canonical: https://modelslab.com/models/anthropic/anthropic-claude-opus-5-fast type: product component: Playground/LLM/Index generated_at: 2026-07-26T01:33:40.286755Z --- Claude Opus 5 (Fast) --- [LLMs.txt](https://modelslab.com/models/anthropic/anthropic-claude-opus-5-fast/llms.txt) [.md](https://modelslab.com/models/anthropic/anthropic-claude-opus-5-fast.md) Claude Opus 5 (Fast) --- Choose a prompt below to get started or type your own message Explain quantum computing in simple terms Write a Python function to sort a list Create a marketing email for a SaaS product Compare REST vs GraphQL APIs Send ### Claude Opus 5 (Fast) anthropic anthropic-claude-opus-5-fast Copy model ID PricingInput $10.00 / 1M tokens Output $50.00 / 1M tokens API EndpointsOpenAI Compatible `https://modelslab.com/api/v7/llm/chat/completions`Endpoint Anthropic Compatible `https://modelslab.com/api/v7/llm/v1/messages`Messages `https://modelslab.com/api/v7/llm/v1/messages/count_tokens`Count Tokens `https://modelslab.com/api/v7/llm/v1/models`Models Use with Claude Code cURL Example ParametersSystem MessageYou are a helpful AI assistant specialized in providing accurate and detailed responses. Temperature0.7 Max Tokens1000 Top P0.9 Frequency Penalty0 Presence Penalty0 Model Info Support Open Source Alternatives --- Similar models we host ourselves — unlimited on the $149/month Open Source Unlimited plan, where this model is billed per call from your wallet [View all open source models](https://modelslab.com/models?feature=llm&provider=open-source-models) [MC Popular](https://modelslab.com/models/modelslab/uncensored-chat)[ModelsLab](https://modelslab.com/models/modelslab) [Modelslab: Custom LLM Open Source Model](https://modelslab.com/models/modelslab/uncensored-chat) Related Models --- Discover similar models you might be interested in [View all LLM Models](https://modelslab.com/models?feature=llmaster) [#### Cohere/Cohere: Command R+ (08-2024) cohere-command-r-plus-08-2024 From $6.25/M tokens](https://modelslab.com/models/cohere/cohere-command-r-plus-08-2024) [#### Meta/Meta: Llama 3.3 70B Instruct meta-llama-llama-3.3-70b-instruct From $0.27/M tokens](https://modelslab.com/models/meta/meta-llama-llama-3.3-70b-instruct) [#### Qwen/Qwen: Qwen3.6 Flash qwen-qwen3.6-flash From $0.66/M tokens](https://modelslab.com/models/qwen/qwen-qwen3.6-flash) [#### Qwen/Qwen: Qwen3 30B A3B Instruct 2507 qwen-qwen3-30b-a3b-instruct-2507 From $0.12/M tokens](https://modelslab.com/models/qwen/qwen-qwen3-30b-a3b-instruct-2507) [#### DeepSeek/DeepSeek: DeepSeek V4 Flash deepseek-deepseek-v4-flash From $0.21/M tokens](https://modelslab.com/models/deepseek/deepseek-deepseek-v4-flash) [#### Anthropic/Anthropic Claude Sonnet Latest anthropic-claude-sonnet-latest From $6.00/M tokens](https://modelslab.com/models/anthropic/anthropic-claude-sonnet-latest) [#### Undi95/ReMM SLERP 13B undi95-remm-slerp-l2-13b From $0.55/M tokens](https://modelslab.com/models/undi95/undi95-remm-slerp-l2-13b) [#### Poolside/Poolside: Laguna M.1 poolside-laguna-m.1 From $0.30/M tokens](https://modelslab.com/models/poolside/poolside-laguna-m.1) [#### StepFun/StepFun: Step 3.7 Flash stepfun-step-3.7-flash From $0.68/M tokens](https://modelslab.com/models/stepfun/stepfun-step-3.7-flash) [#### Cohere/Cohere: North Mini Code (free) cohere-north-mini-code-free Free](https://modelslab.com/models/cohere/cohere-north-mini-code-free) [#### Moonshot AI/MoonshotAI: Kimi K3 moonshotai-kimi-k3 From $9.00/M tokens](https://modelslab.com/models/moonshotai/moonshotai-kimi-k3) [#### Alibaba Cloud/Qwen: Qwen3.5-27B qwen-qwen3.5-27b From $1.35/M tokens](https://modelslab.com/models/alibaba_cloud/qwen-qwen3.5-27b) [#### xAI/xAI: Grok 4.5 x-ai-grok-4.5 From $4.00/M tokens](https://modelslab.com/models/x-ai/x-ai-grok-4.5) [#### Qwen/Qwen: Qwen3.6 35B A3B qwen-qwen3.6-35b-a3b From $0.57/M tokens](https://modelslab.com/models/qwen/qwen-qwen3.6-35b-a3b) [#### Amazon/Amazon: Nova 2 Lite amazon-nova-2-lite-v1 From $1.40/M tokens](https://modelslab.com/models/amazon/amazon-nova-2-lite-v1) [#### Meta/Meta: Llama 3.1 70B Instruct meta-llama-llama-3.1-70b-instruct From $0.40/M tokens](https://modelslab.com/models/meta/meta-llama-llama-3.1-70b-instruct) [#### Qwen/Qwen: Qwen3 235B A22B Thinking 2507 qwen-qwen3-235b-a22b-thinking-2507 From $1.65/M tokens](https://modelslab.com/models/qwen/qwen-qwen3-235b-a22b-thinking-2507) [#### Qwen/Qwen: Qwen3 Max Thinking qwen-qwen3-max-thinking From $2.34/M tokens](https://modelslab.com/models/qwen/qwen-qwen3-max-thinking) 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 IDanthropic-claude-opus-5-fast CategoryLLM Models TaskText Generation Price$30 per million tokens AddedJuly 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](https://modelslab.com/pricing) to get started. PythonJavaScriptcURLPHP ``` import requests import json url = "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](https://modelslab.com/pricing) ### Use Cases - AI chatbots and virtual assistants - Code generation and developer tools - Content writing and copywriting automation - Data analysis, summarization, and extraction [Browse LLM Models](https://modelslab.com/models?feature=llmaster) [More from Anthropic](https://modelslab.com/models/open_router) [View Pricing](https://modelslab.com/pricing) Claude Opus 5 (Fast) FAQ --- ### What is 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 ### How do I use the Claude Opus 5 (Fast) API? 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. ### How much does Claude Opus 5 (Fast) cost? 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. ### What is the Claude Opus 5 (Fast) model ID? 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. ### Do I need a paid plan to use Claude Opus 5 (Fast)? 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. --- *This markdown version is optimized for AI agents and LLMs.* **Links:** - [Website](https://modelslab.com) - [API Documentation](https://docs.modelslab.com) - [Blog](https://modelslab.com/blog) --- *Generated by ModelsLab - 2026-07-26*