Claude Fable 5
VS
Claude Sonnet 4.5
Claude Fable 5 vs Claude Sonnet 4.5: which wins at real work?
22 task areas · same graded test runs · rank comparison only, so 0–100 and Elo collections never mix raw scores.
Claude Fable 5 wins 19 of 22 task areas we tested; Claude Sonnet 4.5 takes 3. Claude Sonnet 4.5 costs 3.3× less per token ($18 vs $60 per 1M).
Claude Sonnet 4.5 costs 3.3× less per token ($18 vs $60 per 1M).
Task by task
| Task area | Claude Fable 5 | Claude Sonnet 4.5 | Winner |
|---|---|---|---|
| Chef / Home Cooking |
#3
/ 126
Strong
|
#80
/ 126
Usable
|
Claude Fable 5 |
| Content & Brand |
#1
/ 124
Excellent
|
#74
/ 124
Usable
|
Claude Fable 5 |
| Legal & HR |
#1
/ 110
Excellent
|
#69
/ 110
Strong
|
Claude Fable 5 |
| AI Strategy |
#1
/ 126
Strong
|
#67
/ 126
Strong
|
Claude Fable 5 |
| Creative & Comedy | #1 / 110 | #66 / 110 | Claude Fable 5 |
| Coding |
#11
/ 115
Excellent
|
#62
/ 115
Strong
|
Claude Fable 5 |
| Customer Support |
#1
/ 113
Excellent
|
#43
/ 113
Strong
|
Claude Fable 5 |
| Investor & Pitch |
#3
/ 66
Strong
|
#42
/ 66
Usable
|
Claude Fable 5 |
| Research & Competitive Analysis |
#3
/ 110
Excellent
|
#39
/ 110
Strong
|
Claude Fable 5 |
| Training & Education |
#16
/ 110
Excellent
|
#51
/ 110
Excellent
|
Claude Fable 5 |
| Data & Analytics |
#3
/ 110
Excellent
|
#33
/ 110
Excellent
|
Claude Fable 5 |
| Frontend & Landing Pages |
#58
/ 109
Needs editing
|
#29
/ 109
Needs editing
|
Claude Sonnet 4.5 |
| Landing Pages |
#1
/ 72
Strong
|
#30
/ 72
Strong
|
Claude Fable 5 |
| Presentations & Decks |
#20
/ 110
Excellent
|
#43
/ 110
Excellent
|
Claude Fable 5 |
| Summarization & Meeting Notes |
#24
/ 110
Excellent
|
#2
/ 110
Excellent
|
Claude Sonnet 4.5 |
| Structured Output |
#68
/ 113
Strong
|
#80
/ 113
Strong
|
Claude Fable 5 |
| Executive Assistant |
#22
/ 112
Strong
|
#31
/ 112
Strong
|
Claude Fable 5 |
| RAG, Safety & Grounding |
#30
/ 113
Excellent
|
#39
/ 113
Excellent
|
Claude Fable 5 |
| Translation & Localization |
#18
/ 110
Excellent
|
#25
/ 110
Excellent
|
Claude Fable 5 |
| Product & Project Management |
#76
/ 110
Strong
|
#71
/ 110
Strong
|
Claude Sonnet 4.5 |
| Sales |
#5
/ 110
Strong
|
#10
/ 110
Strong
|
Claude Fable 5 |
| Knowledge & Docs |
#27
/ 110
Strong
|
#28
/ 110
Strong
|
Claude Fable 5 |
Rank = position among every model config we tested in that task area (lower is better). Sorted by biggest gap first.
Frequently asked
Is Claude Fable 5 better than Claude Sonnet 4.5?
Across 22 task areas we benchmarked, Claude Fable 5 ranks higher in 19 and Claude Sonnet 4.5 in 3.
Which is cheaper, Claude Fable 5 or Claude Sonnet 4.5?
Claude Sonnet 4.5 costs 3.3× less per token ($18 vs $60 per 1M).
What is Claude Fable 5 better at?
Claude Fable 5 out-ranks Claude Sonnet 4.5 at Chef / Home Cooking, Content & Brand, Legal & HR.
What is Claude Sonnet 4.5 better at?
Claude Sonnet 4.5 out-ranks Claude Fable 5 at Frontend & Landing Pages, Summarization & Meeting Notes, Product & Project Management.
More comparisons
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Prompt × model results
12 test cases · 3 evals