Gemini 2.5 Flash Preview vs GPT-4

Compare Gemini 2.5 Flash Preview by Google AI against GPT-4 by OpenAI, context windows of 1.0M vs 8K, tested across 9 shared challenges. Updated April 2026.

Which is better, Gemini 2.5 Flash Preview or GPT-4?

Gemini 2.5 Flash Preview and GPT-4 are both competitive models. Gemini 2.5 Flash Preview costs $0.15/M input tokens vs $30/M for GPT-4. Context windows: 1049K vs 8K tokens. Compare their real outputs side by side below.

Key Differences Between Gemini 2.5 Flash Preview and GPT-4

Gemini 2.5 Flash Preview is made by google while GPT-4 is from openai. Gemini 2.5 Flash Preview has a 1049K token context window compared to GPT-4's 8K. On pricing, Gemini 2.5 Flash Preview costs $0.15/M input tokens vs $30/M for GPT-4.

Our Verdict
Gemini 2.5 Flash Preview
Gemini 2.5 Flash Preview
GPT-4
GPT-4

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 100x cheaper per token — worth considering if cost matters.

Too close to call
Writing DNA

Style Comparison

Similarity
95%

Gemini 2.5 Flash Preview uses 8.8x more headings

Gemini 2.5 Flash Preview
GPT-4
51%Vocabulary59%
15wSentence Length18w
0.70Hedging1.10
4.1Bold0.8
3.3Lists2.5
0.00Emoji0.00
0.09Headings0.00
0.24Transitions0.45
Based on 12 + 15 text responses
vs

Ask them anything yourself

Gemini 2.5 Flash PreviewGPT-4

279 AI models invented the same fake scientist.

We read every word. 250 models. 2.14 million words. This is what we found.

AI Hallucination Index 2026
Free preview13 of 58 slides
FAQ

Common questions