Model Comparison

Claude Sonnet 5 vs Gemini 3.5 FlashWhich is better in 2026?

Claude Sonnet 5 significantly outperforms across most benchmarks. Gemini 3.5 Flash is 1.8x cheaper per token.

Verdict: Claude Sonnet 5 vs Gemini 3.5 Flash — which is better?

Claude Sonnet 5 (by Anthropic) and Gemini 3.5 Flash (by Google) are two of the AI models people compare most. Here is how they stack up on benchmarks, price and capabilities, and which one to pick in 2026.

Claude Sonnet 5 outperforms in 7 benchmarks (CharXiv-R, GDPval-AA, Humanity's Last Exam, Legal Agent Benchmark, OSWorld-Verified, SWE-Bench Pro, Terminal-Bench 2.0), while Gemini 3.5 Flash is better at 1 benchmark (Toolathlon). Claude Sonnet 5 significantly outperforms across most benchmarks.

On price, Gemini 3.5 Flash is roughly 1.8x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.

Gemini 3.5 Flash also accepts a larger context window (1,048,576 input tokens), making it the stronger choice for long documents and large codebases.

Choose Claude Sonnet 5 if…

  • you want the strongest raw capability — it leads on 7 of 8 shared benchmarks
  • you want the most recent training data — it shipped Jun 2026

Choose Gemini 3.5 Flash if…

  • cost matters — it's about 1.8x cheaper per token
  • you process long inputs — it offers a 1,048,576 token context window

Performance Benchmarks

Comparative analysis across standard metrics

8 benchmarks

Claude Sonnet 5 outperforms in 7 benchmarks (CharXiv-R, GDPval-AA, Humanity's Last Exam, Legal Agent Benchmark, OSWorld-Verified, SWE-Bench Pro, Terminal-Bench 2.0), while Gemini 3.5 Flash is better at 1 benchmark (Toolathlon).

Claude Sonnet 5 significantly outperforms across most benchmarks.

Fri Jul 17 2026 • llm-stats.com

Arena Performance

Human preference votes

Pricing Analysis

Price comparison per million tokens

Gemini 3.5 Flash costs less

For input processing, Claude Sonnet 5 ($3.00/1M tokens) is 2.0x more expensive than Gemini 3.5 Flash ($1.50/1M tokens).

For output processing, Claude Sonnet 5 ($15.00/1M tokens) is 1.7x more expensive than Gemini 3.5 Flash ($9.00/1M tokens).

In conclusion, Claude Sonnet 5 is more expensive than Gemini 3.5 Flash.*

* Using a 3:1 ratio of input to output tokens

Lowest available price from all providers
Fri Jul 17 2026 • llm-stats.com
Anthropic
Claude Sonnet 5
Input tokens$3.00
Output tokens$15.00
Best providerAnthropic
Google
Gemini 3.5 Flash
Input tokens$1.50
Output tokens$9.00
Best providerGoogle
Notice missing or incorrect data?Start an Issue→

Context Window

Maximum input and output token capacity

Gemini 3.5 Flash accepts 1,048,576 input tokens compared to Claude Sonnet 5's 1,000,000 tokens. Gemini 3.5 Flash can generate longer responses up to 65,536 tokens, while Claude Sonnet 5 is limited to 64,000 tokens.

Anthropic
Claude Sonnet 5
Input1,000,000 tokens
Output64,000 tokens
Google
Gemini 3.5 Flash
Input1,048,576 tokens
Output65,536 tokens
Fri Jul 17 2026 • llm-stats.com

Input Capabilities

Supported data types and modalities

Both Claude Sonnet 5 and Gemini 3.5 Flash support multimodal inputs.

They are both capable of processing various types of data, offering versatility in application.

Claude Sonnet 5

Text
Images
Audio
Video

Gemini 3.5 Flash

Text
Images
Audio
Video

License

Usage and distribution terms

Both models are licensed under proprietary licenses.

Both models have usage restrictions defined by their respective organizations.

Claude Sonnet 5

Proprietary

Closed source

Gemini 3.5 Flash

Proprietary

Closed source

Release Timeline

When each model was launched

Claude Sonnet 5 was released on 2026-06-30, while Gemini 3.5 Flash was released on 2026-05-19.

Claude Sonnet 5 is 1 month newer than Gemini 3.5 Flash.

Claude Sonnet 5

Jun 30, 2026

2 weeks ago

1mo newer
Gemini 3.5 Flash

May 19, 2026

1 months ago

Knowledge Cutoff

When training data ends

Gemini 3.5 Flash has a documented knowledge cutoff of 2026-01-31, while Claude Sonnet 5's cutoff date is not specified.

We can confirm Gemini 3.5 Flash's training data extends to 2026-01-31, but cannot make a direct comparison without Claude Sonnet 5's cutoff date.

Claude Sonnet 5

—

Gemini 3.5 Flash

Jan 2026

Provider Availability

Claude Sonnet 5 is available from Anthropic. Gemini 3.5 Flash is available from Google.

Claude Sonnet 5

anthropic logo
Anthropic
Input Price:Input: $3.00/1MOutput Price:Output: $15.00/1M

Gemini 3.5 Flash

google logo
Google
Input Price:Input: $1.50/1MOutput Price:Output: $9.00/1M
* Prices shown are per million tokens

Outputs Comparison

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Key Takeaways

Anthropic
Higher CharXiv-R score (88.3% vs 84.2%)
Higher GDPval-AA score (53.9% vs 45.7%)
Higher Humanity's Last Exam score (57.4% vs 40.2%)
Higher Legal Agent Benchmark score (5.8% vs 0.8%)
Higher OSWorld-Verified score (81.2% vs 78.4%)
Higher SWE-Bench Pro score (63.2% vs 55.1%)
Higher Terminal-Bench 2.0 score (80.4% vs 76.2%)
Google
Larger context window (1,048,576 tokens)
Less expensive input tokens
Less expensive output tokens
Higher Toolathlon score (56.5% vs 54.3%)

Detailed Comparison

Interactive Arena

Judge for yourself.

Run your own prompts against Claude Sonnet 5 and Gemini 3.5 Flash side-by-side, then vote on the output you prefer.

Claude Sonnet 5
✓ Preferred
Gemini 3.5 Flash
Open in Playground
AI Model Comparison Table
Feature
Anthropic
Claude Sonnet 5
Google
Gemini 3.5 Flash

FAQ

Common questions about Claude Sonnet 5 vs Gemini 3.5 Flash.

Which is better, Claude Sonnet 5 or Gemini 3.5 Flash?

Claude Sonnet 5 significantly outperforms across most benchmarks. Claude Sonnet 5 is made by Anthropic and Gemini 3.5 Flash is made by Google. The best choice depends on your use case — compare their benchmark scores, pricing, and capabilities above.

How does Claude Sonnet 5 compare to Gemini 3.5 Flash in benchmarks?

Claude Sonnet 5 scores CharXiv-R: 88.3%, ChartMuseum: 86.7%, SWE-Bench Verified: 85.2%, BrowseComp: 84.7%, GDP.pdf: 81.6%. Gemini 3.5 Flash scores CharXiv-R: 84.2%, MCP Atlas: 83.6%, MMMU-Pro: 83.6%, OSWorld-Verified: 78.4%, Terminal-Bench 2.0: 76.2%.

Is Claude Sonnet 5 cheaper than Gemini 3.5 Flash?

Gemini 3.5 Flash is 2.0x cheaper for input tokens. Claude Sonnet 5 costs $3.00/M input and $15.00/M output via anthropic. Gemini 3.5 Flash costs $1.50/M input and $9.00/M output via google.

What are the context window sizes for Claude Sonnet 5 and Gemini 3.5 Flash?

Claude Sonnet 5 supports 1.0M tokens and Gemini 3.5 Flash supports 1.0M tokens. A larger context window lets you process longer documents, conversations, or codebases in a single request.

What are the main differences between Claude Sonnet 5 and Gemini 3.5 Flash?

Key differences include context window (1.0M vs 1.0M), input pricing ($3.00 vs $1.50/M). See the full comparison above for benchmark-by-benchmark results.

Who makes Claude Sonnet 5 and Gemini 3.5 Flash?

Claude Sonnet 5 is developed by Anthropic and Gemini 3.5 Flash is developed by Google.

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