Gemini 1.5 Pro vs Gemini 2.5 Pro Experimental

Compare Gemini 1.5 Pro and Gemini 2.5 Pro Experimental, both from Google AI, in 2 community votes, gemini 1.5 pro and gemini 2.5 pro experimental are closely matched, context windows of 1.0M vs 1.0M, tested across 14 shared challenges. Updated April 2026.

Which is better, Gemini 1.5 Pro or Gemini 2.5 Pro Experimental?

Gemini 1.5 Pro and Gemini 2.5 Pro Experimental are closely matched based on 2 community votes. Gemini 1.5 Pro costs $3.5/M input tokens vs $1/M for Gemini 2.5 Pro Experimental. Context windows: 1000K vs 1000K tokens. Compare their real outputs side by side below.

Key Differences Between Gemini 1.5 Pro and Gemini 2.5 Pro Experimental

Gemini 1.5 Pro is made by google while Gemini 2.5 Pro Experimental is from google. Gemini 1.5 Pro has a 1000K token context window compared to Gemini 2.5 Pro Experimental's 1000K. On pricing, Gemini 1.5 Pro costs $3.5/M input tokens vs $1/M for Gemini 2.5 Pro Experimental. In community voting, In 2 community votes, Gemini 1.5 Pro and Gemini 2.5 Pro Experimental are closely matched.

In 2 community votes, Gemini 1.5 Pro and Gemini 2.5 Pro Experimental are closely matched. Based on blind community voting from the Rival open dataset of 2+ human preference judgments for this pair.

Our Verdict
Gemini 2.5 Pro Experimental
Gemini 2.5 Pro ExperimentalWinner
Gemini 1.5 Pro
Gemini 1.5 ProRunner-up

Votes are tied. Gemini 2.5 Pro Experimental is newer and likely incorporates more recent improvements.

Gemini 2.5 Pro Experimental is 5.3x cheaper per token — worth considering if cost matters.

Too close to call
Writing DNA

Style Comparison

Similarity
100%

Gemini 2.5 Pro Experimental uses 4.8x more headings

Gemini 1.5 Pro
Gemini 2.5 Pro Experimental
61%Vocabulary54%
15wSentence Length15w
0.80Hedging0.35
3.7Bold5.6
3.3Lists3.9
0.00Emoji0.00
0.08Headings0.39
0.09Transitions0.17
Based on 8 + 18 text responses
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Gemini 1.5 ProGemini 2.5 Pro Experimental

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