Claude Fable 5.1 vs Claude Opus 5.5

Which is the better AI model in 2026? Here's how they compare.

Claude Fable 5.1
Anthropic
53.4
Intelligence Index
View Claude Fable 5.1
Higher intelligence
Claude Opus 5.5
Anthropic
57.6
Intelligence Index
View Claude Opus 5.5

Capability profile

Artificial Analysis indices (0–100). Missing dimensions show as 0.

Head to head

Claude Fable 5.1
Claude Opus 5.5
Intelligence
53.4
57.6
Coding
81.6
Math
Context window
1,000,000
1,000,000
Output price
$50/1M
$20/1M
Input price
$10/1M
$4/1M
Speed (t/s)
67
0
Knowledge cutoff
2026-06
2026-06
Open weights
No
No
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