Gemini 1.5 Pro vs GPT-5 Pro

Compare Gemini 1.5 Pro by Google AI against GPT-5 Pro by OpenAI, context windows of 1.0M vs 400K, tested across 14 shared challenges. Updated April 2026.

Which is better, Gemini 1.5 Pro or GPT-5 Pro?

Gemini 1.5 Pro and GPT-5 Pro are both competitive models. Gemini 1.5 Pro costs $3.5/M input tokens vs $15/M for GPT-5 Pro. Context windows: 1000K vs 400K tokens. Compare their real outputs side by side below.

Key Differences Between Gemini 1.5 Pro and GPT-5 Pro

Gemini 1.5 Pro is made by google while GPT-5 Pro is from openai. Gemini 1.5 Pro has a 1000K token context window compared to GPT-5 Pro's 400K. On pricing, Gemini 1.5 Pro costs $3.5/M input tokens vs $15/M for GPT-5 Pro.

Our Verdict
GPT-5 Pro
GPT-5 Pro
Gemini 1.5 Pro
Gemini 1.5 ProRunner-up

No community votes yet. On paper, GPT-5 Pro has the edge — bigger model tier, newer.

Gemini 1.5 Pro is 11x cheaper per token — worth considering if cost matters.

Too close to call
Writing DNA

Style Comparison

Similarity
99%

Gemini 1.5 Pro uses 365.8x more bold

Gemini 1.5 Pro
GPT-5 Pro
61%Vocabulary65%
15wSentence Length15w
0.80Hedging0.32
3.7Bold0.0
3.3Lists2.9
0.00Emoji0.00
0.08Headings0.00
0.09Transitions0.01
Based on 8 + 11 text responses
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Gemini 1.5 ProGPT-5 Pro

279 AI models invented the same fake scientist.

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