What is the difference between Claude Sonnet 4 and Gemini 3.5 Flash?

Claude Sonnet 4 is developed by Anthropic while Gemini 3.5 Flash is developed by Google AI. Claude Sonnet 4 has a 200K token context window vs Gemini 3.5 Flash's 1.0M. You can compare their actual outputs across 53 challenges on Rival to see how they differ in practice.

Which is better, Claude Sonnet 4 or Gemini 3.5 Flash?

It depends on your use case. Claude Sonnet 4 and Gemini 3.5 Flash each have strengths in different areas. Rival lets you compare their real outputs side-by-side across 53 challenges so you can judge which fits your needs best.

How much does Claude Sonnet 4 cost compared to Gemini 3.5 Flash?

Claude Sonnet 4 costs $3/M input tokens and Gemini 3.5 Flash costs $1.5/M input tokens. Gemini 3.5 Flash is $1.50/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 Claude Sonnet 4 and Gemini 3.5 Flash on Rival?

This page shows a side-by-side comparison of Claude Sonnet 4 and Gemini 3.5 Flash 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 Claude Sonnet 4 and Gemini 3.5 Flash?

Claude Sonnet 4 is developed by Anthropic while Gemini 3.5 Flash is developed by Google AI. Claude Sonnet 4 has a 200K token context window vs Gemini 3.5 Flash's 1.0M. You can compare their actual outputs across 53 challenges on Rival to see how they differ in practice.

Which is better, Claude Sonnet 4 or Gemini 3.5 Flash?

It depends on your use case. Claude Sonnet 4 and Gemini 3.5 Flash each have strengths in different areas. Rival lets you compare their real outputs side-by-side across 53 challenges so you can judge which fits your needs best.

How much does Claude Sonnet 4 cost compared to Gemini 3.5 Flash?

Claude Sonnet 4 costs $3/M input tokens and Gemini 3.5 Flash costs $1.5/M input tokens. Gemini 3.5 Flash is $1.50/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 Claude Sonnet 4 and Gemini 3.5 Flash on Rival?

This page shows a side-by-side comparison of Claude Sonnet 4 and Gemini 3.5 Flash 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.

Claude Sonnet 4 vs Gemini 3.5 Flash: Which Is Better?

Updated May 2026

Our Verdict

Gemini 3.5 Flash

Claude Sonnet 4Runner-up

No community votes yet. On paper, Gemini 3.5 Flash has the edge — newer, bigger context window.

Too close to call

API pricing

Cost per 1M tokens

Claude Sonnet 4

Input

$3.00

Output

$15.00

Gemini 3.5 Flash

Input

$1.50

2.0× cheaper

Output

$9.00

1.7× cheaper

Gemini 3.5 Flash is cheaper on both — 2.0× input, 1.7× output

Writing DNA

Style Comparison

Similarity

45%

Claude Sonnet 4 uses 87.9x more emoji

Claude Sonnet 4

Gemini 3.5 Flash

62%Vocabulary59%

111wSentence Length18w

0.40Hedging0.16

5.0Bold4.4

9.3Lists3.0

0.88Emoji0.00

2.16Headings0.89

0.33Transitions0.11

Based on 17 + 27 text responses

Research

What we learned reading every model

Claude Sonnet 4 and Gemini 3.5 Flash 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

Claude Sonnet 4 vs MiniMax M3New provider

Claude Sonnet 4 vs GPT-5New provider

Claude Sonnet 4 vs Meta: Muse Spark 1.1New provider

Updated May 2026

Our Verdict

Gemini 3.5 Flash

Claude Sonnet 4Runner-up

No community votes yet. On paper, Gemini 3.5 Flash has the edge — newer, bigger context window.

Too close to call

API pricing

Cost per 1M tokens

Claude Sonnet 4

Input

$3.00

Output

$15.00

Gemini 3.5 Flash

Input

$1.50

2.0× cheaper

Output

$9.00

1.7× cheaper

Gemini 3.5 Flash is cheaper on both — 2.0× input, 1.7× output

Writing DNA

Style Comparison

Similarity

45%

Claude Sonnet 4 uses 87.9x more emoji

Claude Sonnet 4

Gemini 3.5 Flash

62%Vocabulary59%

111wSentence Length18w

0.40Hedging0.16

5.0Bold4.4

9.3Lists3.0

0.88Emoji0.00

2.16Headings0.89

0.33Transitions0.11

Based on 17 + 27 text responses

Research

What we learned reading every model

Claude Sonnet 4 and Gemini 3.5 Flash 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

Claude Sonnet 4 vs MiniMax M3New provider

Claude Sonnet 4 vs GPT-5New provider

Claude Sonnet 4 vs Meta: Muse Spark 1.1New provider