Polarison

Anthropic

Claude Fable 5.1 pricing and benchmarks

Anthropic’s model for demanding reasoning and long-horizon agentic work.

Input
$10.00
per 1M tokens
Cached input
$0.25
per 1M tokens
Output
$50.00
per 1M tokens
Capability index
164.5
#2 of 16 tracked

How capable is Claude Fable 5.1?

Claude Fable 5.1 scores 164.5 on the Epoch Capabilities Index (confidence interval 161.4–168.3), ranking #2 of the 16 rated models we track.

BenchmarkTestsScore
GPQA DiamondScience reasoning
—
FrontierMath (Tiers 1–3)Advanced math
90.2%
SimpleQA VerifiedFactual accuracy
70.8%
ARC-AGI-2Abstract reasoning
90.0%
DeepSWECoding
—
APEX-AgentsAgentic work
47.4%

Source: Epoch AI (as “Claude Fable 5.1”), best recorded result, CC BY 4.0. A dash means no published score. Compare all models

What Claude Fable 5.1 costs in practice

WorkloadMonthly cost
Support chatbot
100,000 replies a month, ~1,500 input tokens (system prompt + history) and ~400 output tokens each.
$3,500
Document Q&A (RAG)
50,000 questions a month with ~8,000 tokens of retrieved context and ~600 output tokens each.
$5,500
Coding agent
10,000 agent steps a month, ~40,000 input tokens each (70% read from the prompt cache) and ~2,000 output tokens.
$2,270

Pricing details

  • Cache hits cost 2.5% of the base input price, versus 10% on other Claude models.
  • Cache writes cost $12.50 (5-minute cache) or $20 (1-hour cache) per 1M tokens.
  • Uses Anthropic’s newer tokenizer, which produces roughly 30% more tokens for the same text.
  • US-only inference (inference_geo: "us") costs 1.1x.

Estimate your Claude Fable 5.1 bill

Standard-tier list prices. Long-context rates apply automatically where the provider publishes a threshold. Excludes cache-write surcharges, taxes, batch and volume discounts.