TokenTally

Claude Fable 5 vs Claude Opus 4.8: which API costs less?

Averaged across three realistic workloads, Claude Opus 4.8 is about 50% cheaper than Claude Fable 5. Below: raw rates and side-by-side monthly costs, computed from prices verified 2026-07-05 (we track what you are billed today, promos included).

Rates per 1M tokens

ModelInputOutputCached input
Claude Fable 5Anthropic$10$50$1
Claude Opus 4.8Anthropic$5$25$0.500

Claude Fable 5: Najbardziej zaawansowany model.

Monthly cost, side by side

WorkloadClaude Fable 5Claude Opus 4.8Difference

Customer-support chatbot

2M input + 0.5M output tokens/month, 60% of input served from prompt cache

$34.20$17.10Claude Opus 4.850%

RAG / document Q&A

20M input + 1M output tokens/month, 70% cached (shared context)

$124$62.00Claude Opus 4.850%

Agentic coding assistant

50M input + 5M output tokens/month, 80% cached (long sessions)

$390$195Claude Opus 4.850%

Your traffic looks different? Run your own numbers in the calculator.

FAQ

Which is cheaper: Claude Fable 5 or Claude Opus 4.8?

Across three realistic workloads (chatbot, RAG, agent), Claude Opus 4.8 works out about 50% cheaper than Claude Fable 5 on average. Raw rates: Claude Fable 5 $10/$50 per 1M tokens vs Claude Opus 4.8 $5/$25. Verified 2026-07-05.

Does prompt caching change the comparison?

Yes — cached input costs $1 on Claude Fable 5 and $0.500 on Claude Opus 4.8. Our scenario numbers already include realistic cache hit rates.

Is cheaper always better?

No. Price is one axis — model capability, context window and latency differ. This page answers only the cost question; benchmark quality on your own tasks before switching.