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

Compare Gemini 2.5 Flash Preview and Gemini 2.5 Flash Preview 05-20 (thinking), both from Google AI, context windows of 1.0M vs 1.0M, tested across 10 shared challenges. Updated April 2026.

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

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

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

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

Our Verdict
Gemini 2.5 Flash Preview
Gemini 2.5 Flash Preview
Gemini 2.5 Flash Preview 05-20 (thinking)
Gemini 2.5 Flash Preview 05-20 (thinking)

No community votes yet. On paper, these are closely matched - try both with your actual task to see which fits your workflow.

Gemini 2.5 Flash Preview is 5.8x cheaper per token — worth considering if cost matters.

Too close to call
Writing DNA

Style Comparison

Similarity
94%

Gemini 2.5 Flash Preview uses 70.3x more hedging

Gemini 2.5 Flash Preview
Gemini 2.5 Flash Preview 05-20 (thinking)
51%Vocabulary70%
15wSentence Length11w
0.70Hedging0.00
4.1Bold4.2
3.3Lists7.3
0.00Emoji0.00
0.09Headings0.00
0.24Transitions0.00
Based on 12 + 3 text responses
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Gemini 2.5 Flash PreviewGemini 2.5 Flash Preview 05-20 (thinking)

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