Gemini 3.5 Flash
VS
Grok 4.20
Gemini 3.5 Flash 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.
Gemini 3.5 Flash wins 21 of 22 task areas we tested; Grok 4.20 takes 1. Grok 4.20 costs 2.8× less per token ($3.75 vs $10.5 per 1M).
Grok 4.20 costs 2.8× less per token ($3.75 vs $10.5 per 1M).
Task by task
| Task area | Gemini 3.5 Flash | Grok 4.20 | Winner |
|---|---|---|---|
| RAG, Safety & Grounding |
#15
/ 113
Excellent
|
#96
/ 113
Strong
|
Gemini 3.5 Flash |
| Training & Education |
#7
/ 110
Excellent
|
#88
/ 110
Strong
|
Gemini 3.5 Flash |
| Chef / Home Cooking |
#24
/ 126
Usable
|
#100
/ 126
Needs editing
|
Gemini 3.5 Flash |
| Content & Brand |
#46
/ 124
Strong
|
#118
/ 124
Needs editing
|
Gemini 3.5 Flash |
| Creative & Comedy | #27 / 110 | #96 / 110 | Gemini 3.5 Flash |
| Data & Analytics |
#34
/ 110
Excellent
|
#102
/ 110
Excellent
|
Gemini 3.5 Flash |
| Summarization & Meeting Notes |
#17
/ 110
Excellent
|
#85
/ 110
Excellent
|
Gemini 3.5 Flash |
| Translation & Localization |
#30
/ 110
Excellent
|
#98
/ 110
Strong
|
Gemini 3.5 Flash |
| Executive Assistant |
#19
/ 112
Strong
|
#83
/ 112
Usable
|
Gemini 3.5 Flash |
| Coding |
#28
/ 115
Strong
|
#86
/ 115
Usable
|
Gemini 3.5 Flash |
| Customer Support |
#12
/ 113
Strong
|
#68
/ 113
Usable
|
Gemini 3.5 Flash |
| Sales |
#33
/ 110
Strong
|
#85
/ 110
Usable
|
Gemini 3.5 Flash |
| AI Strategy |
#23
/ 126
Strong
|
#59
/ 126
Strong
|
Gemini 3.5 Flash |
| Presentations & Decks |
#17
/ 110
Excellent
|
#46
/ 110
Excellent
|
Gemini 3.5 Flash |
| Knowledge & Docs |
#44
/ 110
Strong
|
#70
/ 110
Usable
|
Gemini 3.5 Flash |
| Landing Pages |
#40
/ 72
Strong
|
#66
/ 72
Usable
|
Gemini 3.5 Flash |
| Product & Project Management |
#33
/ 110
Strong
|
#56
/ 110
Strong
|
Gemini 3.5 Flash |
| Legal & HR |
#73
/ 110
Strong
|
#87
/ 110
Strong
|
Gemini 3.5 Flash |
| Research & Competitive Analysis |
#65
/ 110
Usable
|
#52
/ 110
Usable
|
Grok 4.20 |
| Structured Output |
#35
/ 113
Excellent
|
#48
/ 113
Excellent
|
Gemini 3.5 Flash |
| Frontend & Landing Pages |
#4
/ 109
Usable
|
#15
/ 109
Needs editing
|
Gemini 3.5 Flash |
| Investor & Pitch |
#56
/ 66
Usable
|
#59
/ 66
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.
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
Remote work productivity lessons (Empty Insight Test)
“The response is an expert-level, production-ready output that perfectly adheres to all constraints, provides a highly substantive and specific argument without any fluff, and offers actionable, realistic advice.”
“The response failed the hard constraint on word count by exceeding the 250-word maximum and included unnecessary elements.”
Frequently asked
Is Gemini 3.5 Flash better than Grok 4.20?
Across 22 task areas we benchmarked, Gemini 3.5 Flash ranks higher in 21 and Grok 4.20 in 1.
Which is cheaper, Gemini 3.5 Flash or Grok 4.20?
Grok 4.20 costs 2.8× less per token ($3.75 vs $10.5 per 1M).
What is Gemini 3.5 Flash better at?
Gemini 3.5 Flash out-ranks Grok 4.20 at RAG, Safety & Grounding, Training & Education, Chef / Home Cooking.
What is Grok 4.20 better at?
Grok 4.20 out-ranks Gemini 3.5 Flash at Research & Competitive Analysis.
More comparisons
This page is Spring Prompt, running in public
We just did this for every model. Do it for your prompt.
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Prompt × model results
12 test cases · 3 evals