Claude Sonnet 4.5
VS
Gemini 3 Flash Preview
Claude Sonnet 4.5 vs Gemini 3 Flash Preview: 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 Flash Preview wins 12 of 22 task areas we tested; Claude Sonnet 4.5 takes 10. Gemini 3 Flash Preview costs 5.1× less per token ($3.5 vs $18 per 1M).
Gemini 3 Flash Preview costs 5.1× less per token ($3.5 vs $18 per 1M).
Task by task
| Task area | Claude Sonnet 4.5 | Gemini 3 Flash Preview | Winner |
|---|---|---|---|
| Executive Assistant |
#31
/ 112
Strong
|
#92
/ 112
Usable
|
Claude Sonnet 4.5 |
| Summarization & Meeting Notes |
#2
/ 110
Excellent
|
#61
/ 110
Excellent
|
Claude Sonnet 4.5 |
| Structured Output |
#80
/ 113
Strong
|
#34
/ 113
Excellent
|
Gemini 3 Flash Preview |
| Translation & Localization |
#25
/ 110
Excellent
|
#67
/ 110
Excellent
|
Claude Sonnet 4.5 |
| Chef / Home Cooking |
#80
/ 126
Usable
|
#39
/ 126
Usable
|
Gemini 3 Flash Preview |
| Coding |
#62
/ 115
Strong
|
#22
/ 115
Strong
|
Gemini 3 Flash Preview |
| Training & Education |
#51
/ 110
Excellent
|
#11
/ 110
Excellent
|
Gemini 3 Flash Preview |
| Content & Brand |
#74
/ 124
Usable
|
#39
/ 124
Strong
|
Gemini 3 Flash Preview |
| Research & Competitive Analysis |
#39
/ 110
Strong
|
#71
/ 110
Usable
|
Claude Sonnet 4.5 |
| AI Strategy |
#67
/ 126
Strong
|
#38
/ 126
Strong
|
Gemini 3 Flash Preview |
| Frontend & Landing Pages |
#29
/ 109
Needs editing
|
#1
/ 109
Usable
|
Gemini 3 Flash Preview |
| RAG, Safety & Grounding |
#39
/ 113
Excellent
|
#13
/ 113
Excellent
|
Gemini 3 Flash Preview |
| Sales |
#10
/ 110
Strong
|
#35
/ 110
Usable
|
Claude Sonnet 4.5 |
| Legal & HR |
#69
/ 110
Strong
|
#47
/ 110
Excellent
|
Gemini 3 Flash Preview |
| Knowledge & Docs |
#28
/ 110
Strong
|
#49
/ 110
Usable
|
Claude Sonnet 4.5 |
| Creative & Comedy | #66 / 110 | #51 / 110 | Gemini 3 Flash Preview |
| Data & Analytics |
#33
/ 110
Excellent
|
#47
/ 110
Excellent
|
Claude Sonnet 4.5 |
| Customer Support |
#43
/ 113
Strong
|
#34
/ 113
Strong
|
Gemini 3 Flash Preview |
| Presentations & Decks |
#43
/ 110
Excellent
|
#52
/ 110
Excellent
|
Claude Sonnet 4.5 |
| Investor & Pitch |
#42
/ 66
Usable
|
#47
/ 66
Usable
|
Claude Sonnet 4.5 |
| Landing Pages |
#30
/ 72
Strong
|
#35
/ 72
Strong
|
Claude Sonnet 4.5 |
| Product & Project Management |
#71
/ 110
Strong
|
#69
/ 110
Strong
|
Gemini 3 Flash Preview |
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 Gemini 3 Flash Preview?
Across 22 task areas we benchmarked, Gemini 3 Flash Preview ranks higher in 12 and Claude Sonnet 4.5 in 10.
Which is cheaper, Claude Sonnet 4.5 or Gemini 3 Flash Preview?
Gemini 3 Flash Preview costs 5.1× less per token ($3.5 vs $18 per 1M).
What is Claude Sonnet 4.5 better at?
Claude Sonnet 4.5 out-ranks Gemini 3 Flash Preview at Executive Assistant, Summarization & Meeting Notes, Translation & Localization.
What is Gemini 3 Flash Preview better at?
Gemini 3 Flash Preview out-ranks Claude Sonnet 4.5 at Structured Output, Chef / Home Cooking, Coding.
More comparisons
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Prompt × model results
12 test cases · 3 evals