Gemini 2.5 Flash Preview 05-20 (thinking) vs Gemini 2.5 Pro Preview 06-05

Compare Gemini 2.5 Flash Preview 05-20 (thinking) and Gemini 2.5 Pro Preview 06-05, both from Google AI, context windows of 1.0M vs 1.0M, tested across 11 shared challenges. Updated April 2026.

Which is better, Gemini 2.5 Flash Preview 05-20 (thinking) or Gemini 2.5 Pro Preview 06-05?

Gemini 2.5 Flash Preview 05-20 (thinking) and Gemini 2.5 Pro Preview 06-05 are both competitive models. Gemini 2.5 Flash Preview 05-20 (thinking) costs $0.15/M input tokens vs $1.25/M for Gemini 2.5 Pro Preview 06-05. Context windows: 1049K vs 1049K tokens. Compare their real outputs side by side below.

Key Differences Between Gemini 2.5 Flash Preview 05-20 (thinking) and Gemini 2.5 Pro Preview 06-05

Gemini 2.5 Flash Preview 05-20 (thinking) is made by google while Gemini 2.5 Pro Preview 06-05 is from google. Gemini 2.5 Flash Preview 05-20 (thinking) has a 1049K token context window compared to Gemini 2.5 Pro Preview 06-05's 1049K. On pricing, Gemini 2.5 Flash Preview 05-20 (thinking) costs $0.15/M input tokens vs $1.25/M for Gemini 2.5 Pro Preview 06-05.

Our Verdict
Gemini 2.5 Pro Preview 06-05
Gemini 2.5 Pro Preview 06-05
Gemini 2.5 Flash Preview 05-20 (thinking)
Gemini 2.5 Flash Preview 05-20 (thinking)Runner-up

No community votes yet. On paper, Gemini 2.5 Pro Preview 06-05 has the edge — bigger model tier.

Too close to call
Writing DNA

Style Comparison

Similarity
97%

Gemini 2.5 Pro Preview 06-05 uses 31.3x more hedging

Gemini 2.5 Flash Preview 05-20 (thinking)
Gemini 2.5 Pro Preview 06-05
70%Vocabulary51%
11wSentence Length15w
0.00Hedging0.31
4.2Bold4.8
7.3Lists4.1
0.00Emoji0.00
0.00Headings0.98
0.00Transitions0.05
Based on 3 + 20 text responses
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Gemini 2.5 Flash Preview 05-20 (thinking)Gemini 2.5 Pro Preview 06-05

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