Model Comparison 2026

Claude Fable 5 vs Claude Opus 4.8

Claude Fable 5
Anthropic · Frontier · Proprietary
$22/1M · 1M ctx
Claude Opus 4.8
Anthropic · Frontier · Proprietary
$11/1M · 1M ctx

Community Vote

Pick a winner in each dimension — change your vote anytime.

Output Quality
Correctness and depth of what it produces
Agentic Ability
Tool calls, instruction-following, and multi-step tasks
Speed
Tokens per second and time-to-first-token
Value for $
How much capability you get per dollar
Reliability
Consistent results — fewer refusals, loops, and format breaks

Specs & Pricing, Side by Side

Spec
Fable 5
Opus 4.8
Maker
Anthropic
Anthropic
Blended price / 1M
$22
$11
Input / output
$10 in · $50 out / 1M tokens
$5.00 in · $25 out / 1M tokens
Context window
1M
1M
Open weights
No
No
Tool use
Yes
Yes
Reasoning
Yes
Yes
Output Quality
9.9
9.6
Agentic Ability
9.9
9.6
Speed
6.8
7.2
Value for $
6.8
7.5
Reliability
9.6
9.5

Pricing and capabilities synced from the OpenRouter catalogue. Scores are editorial (0–10).

Verdict: Fable 5 or Opus 4.8?

Updated 2026-07-17

Choose Claude Fable 5 if you want the hardest autonomous coding and reasoning work, where the quality ceiling pays for itself. Choose Claude Opus 4.8 if you want hard, high-stakes coding and reasoning where quality matters more than cost.

In our editorial scoring, Claude Fable 5 leads in 3 of five dimensions (output quality, agentic ability and reliability), while Claude Opus 4.8 leads in 2. On price, Claude Fable 5 runs about $22 per 1M tokens (blended) and is proprietary; Claude Opus 4.8 is about $11 and proprietary.

Where Fable 5 falls short
  • Premium pricing — roughly 2x Opus 4.8 per token
  • Overkill for routine agent steps; escalation-tier economics
Full Fable 5 breakdown →
Where Opus 4.8 falls short
  • Among the most expensive models per token
  • Slower than lighter models on simple tasks
Full Opus 4.8 breakdown →

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