Gemini 3 Flash Preview vs o3 Mini

Compare Gemini 3 Flash Preview by Google AI against o3 Mini by OpenAI, context windows of 1.0M vs 64K, tested across 54 shared challenges. Updated April 2026.

Which is better, Gemini 3 Flash Preview or o3 Mini?

Gemini 3 Flash Preview and o3 Mini are both competitive models. Gemini 3 Flash Preview costs $0.5/M input tokens vs $1.1/M for o3 Mini. Context windows: 1049K vs 64K tokens. Compare their real outputs side by side below.

Key Differences Between Gemini 3 Flash Preview and o3 Mini

Gemini 3 Flash Preview is made by google while o3 Mini is from openai. Gemini 3 Flash Preview has a 1049K token context window compared to o3 Mini's 64K. On pricing, Gemini 3 Flash Preview costs $0.5/M input tokens vs $1.1/M for o3 Mini.

Our Verdict
Gemini 3 Flash Preview
Gemini 3 Flash Preview
o3 Mini
o3 MiniRunner-up

No community votes yet. On paper, Gemini 3 Flash Preview has the edge — bigger model tier, newer, bigger context window.

Slight edge
Writing DNA

Style Comparison

Similarity
92%

o3 Mini uses 5.1x more transitions

Gemini 3 Flash Preview
o3 Mini
55%Vocabulary65%
18wSentence Length17w
0.42Hedging0.74
7.1Bold3.9
4.5Lists1.7
0.00Emoji0.00
0.84Headings0.47
0.07Transitions0.38
Based on 24 + 12 text responses
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Gemini 3 Flash Previewo3 Mini

279 AI models invented the same fake scientist.

We read every word. 250 models. 2.14 million words. This is what we found.

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