- Text Generation
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Claude Opus 4.6 (Fast) is an Anthropic large language model deployment variant that emphasizes reduced latency while retaining strong general-purpose reasoning and generation capabilities. It is designed to provide high-quality answers more quickly than standard Opus configurations.
Output tokens per second · Higher is better
Seconds · Lower is better
USD per 1M tokens (blended) · Lower is better
About the model
Claude Opus 4.6 (Fast) is a performance-optimized configuration of Anthropic’s Claude Opus large language model aimed at delivering fast, capable natural language understanding and generation. It is used for tasks such as interactive chat, drafting and editing text, and answering complex questions with lower response times. It also supports use cases like code assistance, data analysis workflows, and integration into products that require responsive AI features. It belongs to the Claude Opus family of Anthropic frontier models, which are successors to earlier Claude 2.x and Claude 3-series models.
Model capabilities
Engages in complex, context-aware conversations, following nuanced instructions and maintaining coherence over long, multi-turn interactions.
Interprets uploaded images, identifying key elements and relationships to support description, analysis, and problem-solving tasks.
Reads, writes, and improves code in multiple languages, explaining logic, suggesting fixes, and helping debug software issues.
Translates between major languages with attention to tone and context, enabling cross-lingual understanding of documents and messages.
Extracts structured information from documents, screenshots, and other visual text inputs for summarization, analysis, or reformatting.
Use cases
Transparent pricing
Save up to ~70% vs direct Anthropic Claude Opus access
| Provider | Region | Latency | Throughput | Uptime | Input ($/1M) | Output ($/1M) | Context |
|---|---|---|---|---|---|---|---|
| LLM API BEST | Global | 140ms | 120 tps | 99.99% | $6.00 | $18.00 | 200K |
| Anthropic | Global | ~220ms | ~60 tps | 99.9% | ~$18.00 | ~$54.00 | ~200K |
| AWS Bedrock | US East | ~260ms | ~80 tps | 99.9% | ~$19.00 | ~$57.00 | ~200K |
| Google Cloud (Vertex AI) | US Central | ~250ms | ~70 tps | 99.9% | ~$20.00 | ~$60.00 | ~200K |
Performance benchmarks
| Metric | Claude Opus 4.6 (Fast) | OpenAI o4-mini | Google Gemini 1.5 Pro |
|---|---|---|---|
| Avg Latency | ~250ms | ~220ms | ~350ms |
| Context Window | 200K | 128K | 1M |
| Input Price ($/1M) | ~$3.00 | $1.00 | ~$3.50 |
| Output Price ($/1M) | ~$15.00 | $5.00 | ~$10.00 |
| Max Output Tokens | 8K | 16K | 8K |
| Throughput | ~80 tps | ~100 tps | ~70 tps |
| Uptime | ~99.9% | ~99.9% | ~99.9% |
30-day usage via LLM API
Architecture & Integration
One unified API. Every major model. Built-in reliability, cost control, and observability.
Automatically route each request to the best model across providers based on latency, cost, and quality—without changing your integration or redeploying code.
One endpoint, every modelOptimize spend with per-request cost controls, smart model selection, and transparent usage metrics so you can scale AI features without surprise bills.
Lower spend, same outputDefine automatic cross-provider fallbacks to keep your app running through outages, rate limits, and model errors—no custom retry spaghetti required.
Stay online, automaticallyTrace every request across models and providers with logs, timings, and costs in one place, making debugging and performance tuning actually actionable.
See every token hopDescribe high-level tasks instead of wiring raw prompts; LLM.API handles tool calls, model chaining, and state so you ship complex agents with fewer lines.
Ship workflows, not glueRun massive batches of prompts or tasks asynchronously with built-in queuing, retries, and cost tracking—perfect for backfills, evaluations, and data labeling.
Millions of calls, one APIDecision guide
FAQ
Claude Opus 4.6 (Fast) is an Anthropic large language model variant tuned for lower latency while preserving strong reasoning and coding capabilities.
It is best for complex reasoning, multi-step code generation, and production chat agents that need faster responses than standard Claude Opus tiers.
Claude Opus 4.6 (Fast) supports a large-context window suitable for long conversations and multi-file code, as configured by LLM.API.
Claude Opus 4.6 (Fast) is optimized for reduced latency and higher throughput compared to the non-fast Opus variant on LLM.API.
Claude Opus 4.6 (Fast) supports text input and output, and can be used in tool-calling and structured-output workflows via LLM.API.
Specify the model name "claude-opus-4.6-fast" (or equivalent configured identifier) in your LLM.API completion or chat endpoint calls.
It generally offers faster and cheaper responses than the flagship Opus variant while being more capable than smaller Claude models on complex reasoning and coding tasks.
It can still hallucinate, be sensitive to ambiguous prompts, and may be slightly less accurate than the highest-quality Claude Opus 4.6 configuration.
On LLM.API, Claude Opus 4.6 (Fast) is currently available as a text-only model without native image or audio understanding.
Your cost is determined by LLM.API’s per-token pricing for this model, billed separately for input and output tokens according to their posted rates.
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