Claude Sonnet 4.6
VS
Gemini 3.5 Flash
Claude Sonnet 4.6 vs Gemini 3.5 Flash: 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 4.6 wins 13 of 22 task areas we tested; Gemini 3.5 Flash takes 9. Gemini 3.5 Flash costs 1.7× less per token ($10.5 vs $18 per 1M).
Gemini 3.5 Flash costs 1.7× less per token ($10.5 vs $18 per 1M).
Task by task
| Task area | Claude Sonnet 4.6 | Gemini 3.5 Flash | Winner |
|---|---|---|---|
| Legal & HR |
#3
/ 110
Excellent
|
#73
/ 110
Strong
|
Claude Sonnet 4.6 |
| Structured Output |
#105
/ 113
Usable
|
#35
/ 113
Excellent
|
Gemini 3.5 Flash |
| RAG, Safety & Grounding |
#73
/ 113
Excellent
|
#15
/ 113
Excellent
|
Gemini 3.5 Flash |
| Investor & Pitch |
#4
/ 66
Strong
|
#56
/ 66
Usable
|
Claude Sonnet 4.6 |
| Customer Support |
#62
/ 113
Strong
|
#12
/ 113
Strong
|
Gemini 3.5 Flash |
| Landing Pages |
#5
/ 72
Strong
|
#40
/ 72
Strong
|
Claude Sonnet 4.6 |
| Research & Competitive Analysis |
#35
/ 110
Strong
|
#65
/ 110
Usable
|
Claude Sonnet 4.6 |
| Data & Analytics |
#6
/ 110
Excellent
|
#34
/ 110
Excellent
|
Claude Sonnet 4.6 |
| AI Strategy |
#3
/ 126
Strong
|
#23
/ 126
Strong
|
Claude Sonnet 4.6 |
| Sales |
#13
/ 110
Strong
|
#33
/ 110
Strong
|
Claude Sonnet 4.6 |
| Summarization & Meeting Notes |
#37
/ 110
Excellent
|
#17
/ 110
Excellent
|
Gemini 3.5 Flash |
| Frontend & Landing Pages |
#23
/ 109
Needs editing
|
#4
/ 109
Usable
|
Gemini 3.5 Flash |
| Executive Assistant |
#1
/ 112
Strong
|
#19
/ 112
Strong
|
Claude Sonnet 4.6 |
| Presentations & Decks |
#35
/ 110
Excellent
|
#17
/ 110
Excellent
|
Gemini 3.5 Flash |
| Translation & Localization |
#13
/ 110
Excellent
|
#30
/ 110
Excellent
|
Claude Sonnet 4.6 |
| Content & Brand |
#31
/ 124
Strong
|
#46
/ 124
Strong
|
Claude Sonnet 4.6 |
| Product & Project Management |
#48
/ 110
Strong
|
#33
/ 110
Strong
|
Gemini 3.5 Flash |
| Knowledge & Docs |
#35
/ 110
Strong
|
#44
/ 110
Strong
|
Claude Sonnet 4.6 |
| Creative & Comedy | #19 / 110 | #27 / 110 | Claude Sonnet 4.6 |
| Chef / Home Cooking |
#20
/ 126
Usable
|
#24
/ 126
Usable
|
Claude Sonnet 4.6 |
| Training & Education |
#9
/ 110
Excellent
|
#7
/ 110
Excellent
|
Gemini 3.5 Flash |
| Coding |
#29
/ 115
Strong
|
#28
/ 115
Strong
|
Gemini 3.5 Flash |
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 4.6 better than Gemini 3.5 Flash?
Across 22 task areas we benchmarked, Claude Sonnet 4.6 ranks higher in 13 and Gemini 3.5 Flash in 9.
Which is cheaper, Claude Sonnet 4.6 or Gemini 3.5 Flash?
Gemini 3.5 Flash costs 1.7× less per token ($10.5 vs $18 per 1M).
What is Claude Sonnet 4.6 better at?
Claude Sonnet 4.6 out-ranks Gemini 3.5 Flash at Legal & HR, Investor & Pitch, Landing Pages.
What is Gemini 3.5 Flash better at?
Gemini 3.5 Flash out-ranks Claude Sonnet 4.6 at Structured Output, RAG, Safety & Grounding, Customer Support.
More comparisons
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