Claude Fable 5 vs Claude Sonnet 5: API Pricing & Benchmarks

Claude Fable 5 vs Claude Sonnet 5 — or, searched the other way round, Claude Sonnet 5 vs Claude Fable 5: official API prices, what the same workload costs on each, and every published benchmark score, side by side. Every figure comes straight from the data below; this page does not pick a winner.

Price per 1M tokens

Claude Fable 5Claude Sonnet 5
Input$10.00$2.00
Output$50.00$10.00
Blended$20.00$4.00
DeveloperAnthropicAnthropic
Released2026-06-092026-06-30

Prices: official list prices as recorded by models.dev (Claude Fable 5) and models.dev (Claude Sonnet 5).

Cost of the same workload

WorkloadTokensClaude Fable 5Claude Sonnet 5Difference
Short chat reply500 in / 300 out $0.0200 0.4¢ Claude Sonnet 5 cheaper by $0.0160
RAG query4,000 in / 500 out $0.0650 $0.0130 Claude Sonnet 5 cheaper by $0.0520
Long document summary50,000 in / 1,000 out $0.5500 $0.1100 Claude Sonnet 5 cheaper by $0.4400
Code review of a 2k-line file30,000 in / 2,000 out $0.4000 $0.0800 Claude Sonnet 5 cheaper by $0.3200
1,000 chat replies/day for 30 days30,000 × (500 in / 300 out) $600.00 $120.00 Claude Sonnet 5 cheaper by $480.00

Cost = (input tokens ÷ 1,000,000 × input price) + (output tokens ÷ 1,000,000 × output price), using each model's own prices above.

Benchmarks

BenchmarkClaude Fable 5Claude Sonnet 5
Epoch Capabilities Index (ECI) 164.2
epoch · as of 2026-06-09
156.7
epoch · as of 2026-06-30
Epoch Mock AIME accuracy 100.0%
epoch · as of 2026-06-09
94.7%
epoch · as of 2026-06-30
Epoch FrontierMath (T1–3) accuracy 87.0%
epoch · as of 2026-06-09
65.6%
epoch · as of 2026-06-30
Arena text rating 1504
arena · as of 2026-10-28
1462
arena · as of 2026-10-28
Arena coding rating (human preference votes, not task accuracy) 1550
arena · as of 2026-10-28
1520
arena · as of 2026-10-28
Arena math rating 1520
arena · as of 2026-10-28
1475
arena · as of 2026-10-28
Arena WebDev rating 1624
arena · as of 2026-10-28
1540
arena · as of 2026-10-28

Full pages

Claude Fable 5 pricing Claude Sonnet 5 pricing Claude Fable 5 token counter Claude Sonnet 5 token counter

FAQ

Which is cheaper, Claude Fable 5 or Claude Sonnet 5?

Claude Sonnet 5 is cheaper on blended price: $4.00 vs $20.00 per 1M tokens, which is $16.00 less per 1M tokens (80.0% below Claude Fable 5).

How do the input and output prices of Claude Fable 5 and Claude Sonnet 5 compare?

Claude Fable 5 costs $10.00 per 1M input tokens and $50.00 per 1M output tokens. Claude Sonnet 5 costs $2.00 per 1M input tokens and $10.00 per 1M output tokens.

What are the ECI scores of Claude Fable 5 and Claude Sonnet 5?

Claude Fable 5 scores 164.2 on the Epoch Capabilities Index (ECI); Claude Sonnet 5 scores 156.7 on the Epoch Capabilities Index (ECI).

Where does the Claude Fable 5 vs Claude Sonnet 5 comparison data come from?

Prices come from models.dev and LiteLLM (open MIT-licensed catalogs); benchmark scores come from Epoch AI and LMArena (open CC BY 4.0 datasets). This page states the numbers side by side and does not pick an overall winner — see /data-sources/.