Claude Sonnet 5
VS
Gemini 3.5 Flash
Claude Sonnet 5 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.
Gemini 3.5 Flash wins 13 of 22 task areas we tested; Claude Sonnet 5 takes 9. Gemini 3.5 Flash costs 1.1× less per token ($10.5 vs $12 per 1M).
Gemini 3.5 Flash costs 1.1× less per token ($10.5 vs $12 per 1M).
Task by task
| Task area | Claude Sonnet 5 | Gemini 3.5 Flash | Winner |
|---|---|---|---|
| RAG, Safety & Grounding |
#86
/ 113
Excellent
|
#15
/ 113
Excellent
|
Gemini 3.5 Flash |
| Executive Assistant |
#72
/ 112
Strong
|
#19
/ 112
Strong
|
Gemini 3.5 Flash |
| Frontend & Landing Pages |
#57
/ 109
Needs editing
|
#4
/ 109
Usable
|
Gemini 3.5 Flash |
| Creative & Comedy | #79 / 110 | #27 / 110 | Gemini 3.5 Flash |
| Research & Competitive Analysis |
#15
/ 110
Excellent
|
#65
/ 110
Usable
|
Claude Sonnet 5 |
| Customer Support |
#57
/ 113
Strong
|
#12
/ 113
Strong
|
Gemini 3.5 Flash |
| Training & Education |
#52
/ 110
Excellent
|
#7
/ 110
Excellent
|
Gemini 3.5 Flash |
| Summarization & Meeting Notes |
#58
/ 110
Excellent
|
#17
/ 110
Excellent
|
Gemini 3.5 Flash |
| Structured Output |
#69
/ 113
Strong
|
#35
/ 113
Excellent
|
Gemini 3.5 Flash |
| Landing Pages |
#12
/ 72
Strong
|
#40
/ 72
Strong
|
Claude Sonnet 5 |
| Product & Project Management |
#61
/ 110
Strong
|
#33
/ 110
Strong
|
Gemini 3.5 Flash |
| Knowledge & Docs |
#18
/ 110
Strong
|
#44
/ 110
Strong
|
Claude Sonnet 5 |
| Coding |
#6
/ 115
Excellent
|
#28
/ 115
Strong
|
Claude Sonnet 5 |
| AI Strategy |
#2
/ 126
Strong
|
#23
/ 126
Strong
|
Claude Sonnet 5 |
| Content & Brand |
#67
/ 124
Strong
|
#46
/ 124
Strong
|
Gemini 3.5 Flash |
| Data & Analytics |
#16
/ 110
Excellent
|
#34
/ 110
Excellent
|
Claude Sonnet 5 |
| Investor & Pitch |
#39
/ 66
Usable
|
#56
/ 66
Usable
|
Claude Sonnet 5 |
| Sales |
#16
/ 110
Strong
|
#33
/ 110
Strong
|
Claude Sonnet 5 |
| Legal & HR |
#57
/ 110
Excellent
|
#73
/ 110
Strong
|
Claude Sonnet 5 |
| Translation & Localization |
#41
/ 110
Excellent
|
#30
/ 110
Excellent
|
Gemini 3.5 Flash |
| Presentations & Decks |
#22
/ 110
Excellent
|
#17
/ 110
Excellent
|
Gemini 3.5 Flash |
| Chef / Home Cooking |
#28
/ 126
Usable
|
#24
/ 126
Usable
|
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 5 better than Gemini 3.5 Flash?
Across 22 task areas we benchmarked, Gemini 3.5 Flash ranks higher in 13 and Claude Sonnet 5 in 9.
Which is cheaper, Claude Sonnet 5 or Gemini 3.5 Flash?
Gemini 3.5 Flash costs 1.1× less per token ($10.5 vs $12 per 1M).
What is Claude Sonnet 5 better at?
Claude Sonnet 5 out-ranks Gemini 3.5 Flash at Research & Competitive Analysis, Landing Pages, Knowledge & Docs.
What is Gemini 3.5 Flash better at?
Gemini 3.5 Flash out-ranks Claude Sonnet 5 at RAG, Safety & Grounding, Executive Assistant, Frontend & Landing Pages.
More comparisons
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Prompt × model results
12 test cases · 3 evals