Claude Fable 5
VS
Grok 4.20
Claude Fable 5 vs Grok 4.20: 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; Grok 4.20 takes 3. Grok 4.20 costs 16.0× less per token ($3.75 vs $60 per 1M).
Grok 4.20 costs 16.0× less per token ($3.75 vs $60 per 1M).
Task by task
| Task area | Claude Fable 5 | Grok 4.20 | Winner |
|---|---|---|---|
| Content & Brand |
#1
/ 124
Excellent
|
#118
/ 124
Needs editing
|
Claude Fable 5 |
| Data & Analytics |
#3
/ 110
Excellent
|
#102
/ 110
Excellent
|
Claude Fable 5 |
| Chef / Home Cooking |
#3
/ 126
Strong
|
#100
/ 126
Needs editing
|
Claude Fable 5 |
| Creative & Comedy | #1 / 110 | #96 / 110 | Claude Fable 5 |
| Legal & HR |
#1
/ 110
Excellent
|
#87
/ 110
Strong
|
Claude Fable 5 |
| Sales |
#5
/ 110
Strong
|
#85
/ 110
Usable
|
Claude Fable 5 |
| Translation & Localization |
#18
/ 110
Excellent
|
#98
/ 110
Strong
|
Claude Fable 5 |
| Coding |
#11
/ 115
Excellent
|
#86
/ 115
Usable
|
Claude Fable 5 |
| Training & Education |
#16
/ 110
Excellent
|
#88
/ 110
Strong
|
Claude Fable 5 |
| Customer Support |
#1
/ 113
Excellent
|
#68
/ 113
Usable
|
Claude Fable 5 |
| RAG, Safety & Grounding |
#30
/ 113
Excellent
|
#96
/ 113
Strong
|
Claude Fable 5 |
| Landing Pages |
#1
/ 72
Strong
|
#66
/ 72
Usable
|
Claude Fable 5 |
| Executive Assistant |
#22
/ 112
Strong
|
#83
/ 112
Usable
|
Claude Fable 5 |
| Summarization & Meeting Notes |
#24
/ 110
Excellent
|
#85
/ 110
Excellent
|
Claude Fable 5 |
| AI Strategy |
#1
/ 126
Strong
|
#59
/ 126
Strong
|
Claude Fable 5 |
| Investor & Pitch |
#3
/ 66
Strong
|
#59
/ 66
Usable
|
Claude Fable 5 |
| Research & Competitive Analysis |
#3
/ 110
Excellent
|
#52
/ 110
Usable
|
Claude Fable 5 |
| Frontend & Landing Pages |
#58
/ 109
Needs editing
|
#15
/ 109
Needs editing
|
Grok 4.20 |
| Knowledge & Docs |
#27
/ 110
Strong
|
#70
/ 110
Usable
|
Claude Fable 5 |
| Presentations & Decks |
#20
/ 110
Excellent
|
#46
/ 110
Excellent
|
Claude Fable 5 |
| Product & Project Management |
#76
/ 110
Strong
|
#56
/ 110
Strong
|
Grok 4.20 |
| Structured Output |
#68
/ 113
Strong
|
#48
/ 113
Excellent
|
Grok 4.20 |
Rank = position among every model config we tested in that task area (lower is better). Sorted by biggest gap first.
Same task, both models — judged
Both models answered the same test case; an independent judge graded each. Quotes are the judge's actual rationale.
Content & Brand
Customer research beats internal opinions (Empty Insight Test)
“The response perfectly executes the prompt, providing a highly specific and realistic example, an actionable recommendation, and excellent rhetorical punch, all while strictly adhering to the word count constraint. It successfully avoids the 'polished emptiness' failure mode.”
“The response exceeded the maximum word count constraint with approximately 267 words.”
Frequently asked
Is Claude Fable 5 better than Grok 4.20?
Across 22 task areas we benchmarked, Claude Fable 5 ranks higher in 19 and Grok 4.20 in 3.
Which is cheaper, Claude Fable 5 or Grok 4.20?
Grok 4.20 costs 16.0× less per token ($3.75 vs $60 per 1M).
What is Claude Fable 5 better at?
Claude Fable 5 out-ranks Grok 4.20 at Content & Brand, Data & Analytics, Chef / Home Cooking.
What is Grok 4.20 better at?
Grok 4.20 out-ranks Claude Fable 5 at Frontend & Landing Pages, Product & Project Management, Structured Output.
More comparisons
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Prompt × model results
12 test cases · 3 evals