What is Claude Fable 5?
Claude Fable 5 (model id claude-fable-5) launched on June 9, 2026 as Anthropic's most capable widely released model. It targets the hardest reasoning and long-horizon agentic work — tasks that run for hours or days across many tool calls. It ships with a 1M-token context window, up to 128K output tokens per request, and built-in safety classifiers that can return a refusal as a normal 200 response.
Claude Fable 5 pricing
Fable 5 is priced at $10 per 1M input tokens and $50 per 1M output tokens. That's premium-tier: roughly 3x the input cost of Claude Opus 4.6 and far above mid-tier models. For a single 2,000-in / 800-out request that's about $0.06 — fine for one call, expensive once you run agents in a loop.
Is Fable 5 worth it?
If your workload genuinely needs frontier long-horizon autonomy and a wrong answer is costly, Fable 5 earns its price. For the other 90% of production work — coding assistants, chat, content, retrieval — a cheaper model gets you most of the way at a tenth of the cost.
The cheaper path: Fable-5-class work on KissAPI
KissAPI focuses on the models most teams actually ship on, at up to 80% off list price. For demanding work you'd otherwise throw at Fable 5, Claude Opus 4.8 and Claude Sonnet 5 cover the vast majority of real tasks for far less, and everything runs behind one OpenAI-compatible endpoint.
curl https://api.kissapi.ai/v1/chat/completions \
-H "Authorization: Bearer $KISSAPI_KEY" \
-H "Content-Type: application/json" \
-d '{"model":"claude-opus-4-8","messages":[{"role":"user","content":"hi"}]}'Want native Fable 5 / Mythos 5 access added to KissAPI? It's on our evaluation list — create an account and tell us your use case.
Get frontier-class results for less
Run Claude Opus 4.8, Sonnet 5, GPT-5.5 and more behind one key. $1 free credit to start.
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How much does Claude Fable 5 cost?
Claude Fable 5 is priced at $10 per 1M input tokens and $50 per 1M output tokens, with a 1M-token context window and up to 128K output tokens per request.
When was Claude Fable 5 released?
Anthropic released Claude Fable 5 on June 9, 2026, alongside the limited-release Claude Mythos 5. It's available on the Claude API, Amazon Bedrock, Google Cloud, and Microsoft Foundry.
What's a cheaper alternative to Claude Fable 5?
For most production workloads, Claude Opus 4.8 or Claude Sonnet 5 deliver frontier-class quality at a fraction of Fable 5's price. KissAPI offers these behind one OpenAI-compatible endpoint at up to 80% off list pricing.
Does KissAPI offer Claude Fable 5?
Not yet. KissAPI currently serves Claude Opus 4.8, Sonnet 5, GPT-5.5 and more. Native Fable 5 access is under evaluation — sign up and let us know if you need it.