Gemini 1.5 Pro vs GPT-4.5

Compare Gemini 1.5 Pro by Google AI against GPT-4.5 by OpenAI, context windows of 1.0M vs 128K, tested across 12 shared challenges. Updated March 2026.

Which is better, Gemini 1.5 Pro or GPT-4.5?

Gemini 1.5 Pro and GPT-4.5 are both competitive models. Gemini 1.5 Pro costs $3.5/M input tokens vs $75/M for GPT-4.5. Context windows: 1000K vs 128K tokens. Compare their real outputs side by side below.

Key Differences Between Gemini 1.5 Pro and GPT-4.5

Gemini 1.5 Pro is made by google while GPT-4.5 is from openai. Gemini 1.5 Pro has a 1000K token context window compared to GPT-4.5's 128K. On pricing, Gemini 1.5 Pro costs $3.5/M input tokens vs $75/M for GPT-4.5.

Our Verdict
GPT-4.5
GPT-4.5
Gemini 1.5 Pro
Gemini 1.5 ProRunner-up

No community votes yet. On paper, GPT-4.5 has the edge — bigger model tier, newer.

Gemini 1.5 Pro is 14x cheaper per token — worth considering if cost matters.

Too close to call
Writing DNA

Style Comparison

Similarity
95%

GPT-4.5 uses 16.1x more headings

Gemini 1.5 Pro
GPT-4.5
61%Vocabulary63%
15wSentence Length16w
0.80Hedging0.57
3.7Bold4.7
3.3Lists6.4
0.00Emoji0.00
0.08Headings1.30
0.09Transitions0.54
Based on 8 + 11 text responses
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