Claude Fable 5 vs Claude Opus 5.5 (Adaptive Reasoning, Medium Effort, Default Fallback)
Wins 2 of 6 areas
Coding · Facts
Wins 2 of 6 areas
Images and charts · Long documents
The two are evenly matched.Claude Fable 5 is better at facts and coding; Claude Opus 5.5 (Adaptive Reasoning, Medium Effort, Default Fallback) at images and charts and long documents.
Scores updated · 11 tests both models report · How we compare
Where each one wins
Tests won in each of the six areas where both have results. Each piece is one test, so a longer bar means more evidence; grey means the two scored within a point of each other.
- FactsGetting facts right instead of making them up10Claude Fable 51 of 2 tests · 1 tie
- CodingWriting and fixing software10Claude Fable 51 of 1 test
- Images and chartsUnderstanding pictures, charts and video01Claude Opus 5.5 (Adaptive Reasoning, Medium Effort, Default Fallback)1 of 1 test
- Long documentsFinding answers in very long texts01Claude Opus 5.5 (Adaptive Reasoning, Medium Effort, Default Fallback)1 of 1 test
- AgentsCarrying out multi-step tasks on its own11Even1 each
- ReasoningHard problems that need careful thinking00Even0 each · 2 ties
Coding, images and charts and long documents rest on a single test each.
What it costs
Prices per million tokens, roughly 750,000 words. The bars show the cost of a million tokens read plus a million written.
Claude Opus 5.5 (Adaptive Reasoning, Medium Effort, Default Fallback) costs 60% less for the same work.
The biggest differences
The three tests each model wins by the widest margin. Scores are out of 100.
Where Claude Fable 5 pulls ahead
- Avoids making up answers it doesn't knowAA-Omniscience · Non-hallucination+4.8points ahead
- Code for real scientific research problemsSciCode+1.7points ahead
- Real work tasks from 44 professionsGDPVal+1.3points ahead
Every test, side by side
All 11 tests both models report. The winning score is in its model's colour; marks a score checked independently.
AgentsEven
- Terminal-Bench 4.0Claude Opus 5.5 (Adaptive Reasoning, Medium Effort, Default Fallback) by 10.142.452.5+10.1
- GDPValClaude Fable 5 by 1.355.654.3+1.3
FactsClaude Fable 5
- AA-Omniscience · Non-hallucinationClaude Fable 5 by 4.836.431.6+4.8
- AA-Omniscience · Accuracytie65.364.5tie
Images and chartsClaude Opus 5.5 (Adaptive Reasoning, Medium Effort, Default Fallback)
- MMMU-ProClaude Opus 5.5 (Adaptive Reasoning, Medium Effort, Default Fallback) by 1.584.285.7+1.5
Long documentsClaude Opus 5.5 (Adaptive Reasoning, Medium Effort, Default Fallback)
- AA-LCRClaude Opus 5.5 (Adaptive Reasoning, Medium Effort, Default Fallback) by 282.384.3+2
Other results2 tests, not counted
Tests outside the eight areas. They are not counted above: several are summary scores built from other tests, or the same test under another name.
- AA-OmniscienceClaude Fable 5 by 343.340.3+3
- AA IntelligenceClaude Opus 5.5 (Adaptive Reasoning, Medium Effort, Default Fallback) by 1.649.651.2+1.6
Questions people ask
Which is better, Claude Fable 5 or Claude Opus 5.5 (Adaptive Reasoning, Medium Effort, Default Fallback)?
Claude Fable 5 and Claude Opus 5.5 (Adaptive Reasoning, Medium Effort, Default Fallback) each win two of the six areas where both have results. Claude Fable 5 wins coding and facts; Claude Opus 5.5 (Adaptive Reasoning, Medium Effort, Default Fallback) wins images and charts and long documents. Claude Opus 5.5 (Adaptive Reasoning, Medium Effort, Default Fallback) costs 60% less. They are level on agents and reasoning.
Which is better for coding?
Claude Fable 5. It wins the one coding test both models report.
Which is cheaper?
Claude Fable 5 costs $10.00 per million input tokens and $50.00 per million output tokens; Claude Opus 5.5 (Adaptive Reasoning, Medium Effort, Default Fallback) costs $4.00 and $20.00. That makes Claude Opus 5.5 (Adaptive Reasoning, Medium Effort, Default Fallback) about 60% cheaper for the same work.
How do you compare the two?
We use the 11 benchmark tests both models have published scores on. The verdict counts the 9 tests in the eight capability areas, and a gap under one point (ten on rating-style scales) counts as a tie. The other 2 are listed but not counted, because several are summary scores or repeat a test. Each score is the one shown on the model's own page.