Claude Sonnet 4.5
VS
Grok 4.20
Claude Sonnet 4.5 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 Sonnet 4.5 wins 18 of 22 task areas we tested; Grok 4.20 takes 4. Grok 4.20 costs 4.8× less per token ($3.75 vs $18 per 1M).
Grok 4.20 costs 4.8× less per token ($3.75 vs $18 per 1M).
Task by task
| Task area | Claude Sonnet 4.5 | Grok 4.20 | Winner |
|---|---|---|---|
| Summarization & Meeting Notes |
#2
/ 110
Excellent
|
#85
/ 110
Excellent
|
Claude Sonnet 4.5 |
| Sales |
#10
/ 110
Strong
|
#85
/ 110
Usable
|
Claude Sonnet 4.5 |
| Translation & Localization |
#25
/ 110
Excellent
|
#98
/ 110
Strong
|
Claude Sonnet 4.5 |
| Data & Analytics |
#33
/ 110
Excellent
|
#102
/ 110
Excellent
|
Claude Sonnet 4.5 |
| RAG, Safety & Grounding |
#39
/ 113
Excellent
|
#96
/ 113
Strong
|
Claude Sonnet 4.5 |
| Executive Assistant |
#31
/ 112
Strong
|
#83
/ 112
Usable
|
Claude Sonnet 4.5 |
| Content & Brand |
#74
/ 124
Usable
|
#118
/ 124
Needs editing
|
Claude Sonnet 4.5 |
| Knowledge & Docs |
#28
/ 110
Strong
|
#70
/ 110
Usable
|
Claude Sonnet 4.5 |
| Training & Education |
#51
/ 110
Excellent
|
#88
/ 110
Strong
|
Claude Sonnet 4.5 |
| Landing Pages |
#30
/ 72
Strong
|
#66
/ 72
Usable
|
Claude Sonnet 4.5 |
| Structured Output |
#80
/ 113
Strong
|
#48
/ 113
Excellent
|
Grok 4.20 |
| Creative & Comedy | #66 / 110 | #96 / 110 | Claude Sonnet 4.5 |
| Customer Support |
#43
/ 113
Strong
|
#68
/ 113
Usable
|
Claude Sonnet 4.5 |
| Coding |
#62
/ 115
Strong
|
#86
/ 115
Usable
|
Claude Sonnet 4.5 |
| Chef / Home Cooking |
#80
/ 126
Usable
|
#100
/ 126
Needs editing
|
Claude Sonnet 4.5 |
| Legal & HR |
#69
/ 110
Strong
|
#87
/ 110
Strong
|
Claude Sonnet 4.5 |
| Investor & Pitch |
#42
/ 66
Usable
|
#59
/ 66
Usable
|
Claude Sonnet 4.5 |
| Product & Project Management |
#71
/ 110
Strong
|
#56
/ 110
Strong
|
Grok 4.20 |
| Frontend & Landing Pages |
#29
/ 109
Needs editing
|
#15
/ 109
Needs editing
|
Grok 4.20 |
| Research & Competitive Analysis |
#39
/ 110
Strong
|
#52
/ 110
Usable
|
Claude Sonnet 4.5 |
| AI Strategy |
#67
/ 126
Strong
|
#59
/ 126
Strong
|
Grok 4.20 |
| Presentations & Decks |
#43
/ 110
Excellent
|
#46
/ 110
Excellent
|
Claude Sonnet 4.5 |
Rank = position among every model config we tested in that task area (lower is better). Sorted by biggest gap first.
Frequently asked
Is Claude Sonnet 4.5 better than Grok 4.20?
Across 22 task areas we benchmarked, Claude Sonnet 4.5 ranks higher in 18 and Grok 4.20 in 4.
Which is cheaper, Claude Sonnet 4.5 or Grok 4.20?
Grok 4.20 costs 4.8× less per token ($3.75 vs $18 per 1M).
What is Claude Sonnet 4.5 better at?
Claude Sonnet 4.5 out-ranks Grok 4.20 at Summarization & Meeting Notes, Sales, Translation & Localization.
What is Grok 4.20 better at?
Grok 4.20 out-ranks Claude Sonnet 4.5 at Structured Output, Product & Project Management, Frontend & Landing Pages.
More comparisons
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Prompt × model results
12 test cases · 3 evals