What is the difference between Gemini 3.5 Flash and GPT-4.5?

Gemini 3.5 Flash is developed by Google AI while GPT-4.5 is developed by OpenAI. Gemini 3.5 Flash has a 1.0M token context window vs GPT-4.5's 128K. You can compare their actual outputs across 24 challenges on Rival to see how they differ in practice.

Which is better, Gemini 3.5 Flash or GPT-4.5?

It depends on your use case. Gemini 3.5 Flash and GPT-4.5 each have strengths in different areas. Rival lets you compare their real outputs side-by-side across 24 challenges so you can judge which fits your needs best.

How much does Gemini 3.5 Flash cost compared to GPT-4.5?

Gemini 3.5 Flash costs $1.5/M input tokens and GPT-4.5 costs $75/M input tokens. Gemini 3.5 Flash is $73.50/M cheaper per input. Check their side-by-side outputs on Rival to see if the price difference is justified by quality.

How can I compare Gemini 3.5 Flash and GPT-4.5 on Rival?

This page shows a side-by-side comparison of Gemini 3.5 Flash and GPT-4.5 across shared challenges. You can vote on which model produced the better output in a blind duel. Browsing and voting are free. No account is needed to look; signing in only saves your votes and likes.

What is the difference between Gemini 3.5 Flash and GPT-4.5?

Gemini 3.5 Flash is developed by Google AI while GPT-4.5 is developed by OpenAI. Gemini 3.5 Flash has a 1.0M token context window vs GPT-4.5's 128K. You can compare their actual outputs across 24 challenges on Rival to see how they differ in practice.

Which is better, Gemini 3.5 Flash or GPT-4.5?

It depends on your use case. Gemini 3.5 Flash and GPT-4.5 each have strengths in different areas. Rival lets you compare their real outputs side-by-side across 24 challenges so you can judge which fits your needs best.

How much does Gemini 3.5 Flash cost compared to GPT-4.5?

Gemini 3.5 Flash costs $1.5/M input tokens and GPT-4.5 costs $75/M input tokens. Gemini 3.5 Flash is $73.50/M cheaper per input. Check their side-by-side outputs on Rival to see if the price difference is justified by quality.

How can I compare Gemini 3.5 Flash and GPT-4.5 on Rival?

This page shows a side-by-side comparison of Gemini 3.5 Flash and GPT-4.5 across shared challenges. You can vote on which model produced the better output in a blind duel. Browsing and voting are free. No account is needed to look; signing in only saves your votes and likes.

Gemini 3.5 Flash vs GPT-4.5: Which Is Better?

Updated May 2026

Our Verdict

Gemini 3.5 Flash

GPT-4.5

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

Gemini 3.5 Flash is 17x cheaper per token — worth considering if cost matters.

Too close to call

API pricing

Cost per 1M tokens

Gemini 3.5 Flash

Input

$1.50

50× cheaper

Output

$9.00

17× cheaper

GPT-4.5

Input

$75.00

Output

$150.00

Gemini 3.5 Flash is cheaper on both — 50× input, 17× output

Writing DNA

Style Comparison

Similarity

40%

GPT-4.5 uses 5.0x more transitions

Gemini 3.5 Flash

GPT-4.5

59%Vocabulary63%

18wSentence Length16w

0.16Hedging0.57

4.4Bold4.7

3.0Lists6.4

0.00Emoji0.00

0.89Headings1.30

0.11Transitions0.54

Based on 27 + 11 text responses

Research

What we learned reading every model

Gemini 3.5 Flash and GPT-4.5 have opinions about your brand too.Ask 10 models what they tell people about you. Verbatim receipts.Run the mirror

FAQ

Common questions

Keep exploring

More comparisons

GPT-4.5 vs MiniMax M3New provider

GPT-4.5 vs Meta: Muse Spark 1.1New provider

Gemini 3.5 Flash vs GPT-5Cross-provider

Updated May 2026

Our Verdict

Gemini 3.5 Flash

GPT-4.5

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

Gemini 3.5 Flash is 17x cheaper per token — worth considering if cost matters.

Too close to call

API pricing

Cost per 1M tokens

Gemini 3.5 Flash

Input

$1.50

50× cheaper

Output

$9.00

17× cheaper

GPT-4.5

Input

$75.00

Output

$150.00

Gemini 3.5 Flash is cheaper on both — 50× input, 17× output

Writing DNA

Style Comparison

Similarity

40%

GPT-4.5 uses 5.0x more transitions

Gemini 3.5 Flash

GPT-4.5

59%Vocabulary63%

18wSentence Length16w

0.16Hedging0.57

4.4Bold4.7

3.0Lists6.4

0.00Emoji0.00

0.89Headings1.30

0.11Transitions0.54

Based on 27 + 11 text responses

Research

What we learned reading every model

Gemini 3.5 Flash and GPT-4.5 have opinions about your brand too.Ask 10 models what they tell people about you. Verbatim receipts.Run the mirror

FAQ

Common questions

Keep exploring

More comparisons

GPT-4.5 vs MiniMax M3New provider

GPT-4.5 vs Meta: Muse Spark 1.1New provider

Gemini 3.5 Flash vs GPT-5Cross-provider