Claude Sonnet 4.6 vs Gemini 3.5 Flash

Claude Sonnet 4.6 and Gemini 3.5 Flash are both current production-tier models. Gemini 3.5 Flash is meaningfully cheaper at $1.5 / $9 per 1M. Claude Sonnet 4.6 leads on tool use. Gemini 3.5 Flash leads on multilingual, vision.

Specs side by side

Metric
Anthropic
Claude Sonnet 4.6
Google
Gemini 3.5 Flash
Input price (per 1M)$3$1.5
Output price (per 1M)$15$9
Context window1M tokens1.0M tokens
Speed tierbalancedfast
Open weightsNoNo
EU regionYesYes
Free tierNoGoogle AI Studio
Prompt cachingYesYes
Vision inputYesYes
Extended thinkingYesYes

When to choose each

Anthropic

Choose Claude Sonnet 4.6 if…

  • Tool use is central to your workload
Google Free tier

Choose Gemini 3.5 Flash if…

  • You want a free tier for prototyping
  • Multilingual is central to your workload
  • Vision is central to your workload

Benchmark delta

Claude Sonnet 4.6 leads on

  • Tool use

Gemini 3.5 Flash leads on

  • Multilingual
  • Vision

FAQ — Claude Sonnet 4.6 vs Gemini 3.5 Flash

Claude Sonnet 4.6 vs Gemini 3.5 Flash — which is better?

Claude Sonnet 4.6 and Gemini 3.5 Flash are both current production-tier models. Gemini 3.5 Flash is meaningfully cheaper at $1.5 / $9 per 1M. Claude Sonnet 4.6 leads on tool use. Gemini 3.5 Flash leads on multilingual, vision. The right pick depends on your use case — see "When to choose each" above for a data-driven decision.

How does Claude Sonnet 4.6 pricing compare to Gemini 3.5 Flash?

Claude Sonnet 4.6 costs $3 / $15 per 1M vs Gemini 3.5 Flash at $1.5 / $9 per 1M. Gemini 3.5 Flash is cheaper on output tokens by roughly 67%. Both support prompt caching, which reduces effective cost by 80-90% on repeat system prompts.

Does Claude Sonnet 4.6 or Gemini 3.5 Flash have the bigger context window?

Gemini 3.5 Flash has a 1.0M-token context window — 1× the 1M context of Claude Sonnet 4.6. Enough for entire codebases, books, or multi-document RAG.

Is there a free tier for Claude Sonnet 4.6 or Gemini 3.5 Flash?

Claude Sonnet 4.6: no — Free via Claude.ai web chat; API requires paid credits. Gemini 3.5 Flash: yes — Reduced daily quota via AI Studio for prototyping.

Which is better for coding — Claude Sonnet 4.6 or Gemini 3.5 Flash?

Claude Sonnet 4.6 leads on coding benchmarks (Claude Sonnet 4.6: 94/100, Gemini 3.5 Flash: 91/100). For production coding agents also weigh tool-use performance — Claude Sonnet 4.6 scores 96, Gemini 3.5 Flash scores 90.