Last refreshed 2026-09-01. Next refresh: weekly.
Why use Claude Fable 5.1 on OpenRouter?
OpenRouter offers Claude Fable 5.1 with pay-as-you-go pricing at $10.00/1M input tokens. OpenRouter is a multi-provider LLM aggregator offering unified API access to 300+ models from all major labs and emerging providers, with automatic failover for reliability.
Compare Claude Fable 5.1 across 5 providers to find the best fit for your use caseSetup recipe
Docs fallbackUse the provider REST API or SDKCreate a provider API keymodel: anthropic/claude-fable-5.1anthropic/claude-fable-5.1Request example
anthropic/claude-fable-5.1.Gotchas
- Use provider model ID "anthropic/claude-fable-5.1", not the LLMReference slug "claude-fable-5-1".
Compare Claude Fable 5.1 Across Providers
| Provider | Input (per 1M) | Output (per 1M) |
|---|---|---|
| Anthropic | $10.00 | $50.00 |
| AWS Bedrock | $10.00 | $50.00 |
| GCP Vertex AI | $10.00 | $50.00 |
| Microsoft Foundry | $10.00 | $50.00 |
| OpenRouter | $10.00 | $50.00 |
Pricing
| Type | Price (per 1M) |
|---|---|
| Input tokens | $10.00 |
| Output tokens | $50.00 |
Capabilities
About Claude Fable 5.1
Anthropic's generally available Mythos-class model for demanding reasoning, long-horizon agents, and ambitious coding, released September 1, 2026. Same underlying model as Claude Mythos 5.1 with cybersecurity and biology safeguards (flagged queries route to Opus 4.8 for cyber and Opus 5 for biology; those reroutes are not billed at Fable prices). Claude API id claude-fable-5-1. List price $10 per 1M input tokens and $50 per 1M output tokens; cache reads $0.25 per 1M (0.025x base input, 75% less than Fable 5's $1.00).