Claude Sonnet 4.5 vs Gemini 3 Flash
Side-by-side benchmark comparison across coding, math, reasoning, speed, and pricing.
Gemini 3 Flash by Google wins on 10 of 16 benchmarks against Claude Sonnet 4.5 by Anthropic, which leads on 6. This head-to-head comparison covers coding, math, reasoning, speed, and pricing metrics from our benchmark data.
Category-by-Category Breakdown
General Intelligence: In general intelligence, Gemini 3 Flash scores 1473 on Chatbot Arena ELO compared to Claude Sonnet 4.5's 1380, while Gemini 3 Flash scores 88.6% on MMLU-Pro compared to Claude Sonnet 4.5's 83.0%, while Gemini 3 Flash scores 89.0% on IFEval compared to Claude Sonnet 4.5's 88.0%.
Coding: In coding, Claude Sonnet 4.5 scores 90.0% on HumanEval+ compared to Gemini 3 Flash's 86.0%, while Gemini 3 Flash scores 78.0% on SWE-bench Verified compared to Claude Sonnet 4.5's 77.2%, while Claude Sonnet 4.5 scores 62.0% on LiveCodeBench compared to Gemini 3 Flash's 55.0%.
Math: In math, Claude Sonnet 4.5 scores 87.0% on MATH compared to Gemini 3 Flash's 85.0%, while Claude Sonnet 4.5 scores 95.5% on GSM8K compared to Gemini 3 Flash's 95.0%.
Reasoning: In reasoning, Claude Sonnet 4.5 scores 83.4% on GPQA Diamond compared to Gemini 3 Flash's 72.0%, while Claude Sonnet 4.5 scores 45.0% on ARC-AGI compared to Gemini 3 Flash's 30.0%.
Context: In context, Gemini 3 Flash scores 1.0M on Context Length compared to Claude Sonnet 4.5's 1.0M.
Pricing Comparison
Claude Sonnet 4.5 costs $3.0/1M input tokens and $15.0/1M output tokens, while Gemini 3 Flash costs $0.50/1M input and $3.0/1M output. Gemini 3 Flash is the more affordable option for API usage.
Speed Comparison
Claude Sonnet 4.5 generates output at 67 tok/s compared to Gemini 3 Flash's 200 tok/s, and the time to first token is 1170 ms for Claude Sonnet 4.5 versus 100 ms for Gemini 3 Flash. Gemini 3 Flash delivers faster throughput.
Verdict
For developers prioritizing math, Claude Sonnet 4.5 has the edge. For those who value coding and general intelligence and affordability and speed, Gemini 3 Flash is the stronger choice.
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Claude Sonnet 4.5 vs Gemini 3 Flash — FAQ
Which is better, Claude Sonnet 4.5 or Gemini 3 Flash?
Gemini 3 Flash wins on more benchmarks overall (10 vs 6). However, the best choice depends on your specific needs — each model excels in different areas.
How does Claude Sonnet 4.5 compare to Gemini 3 Flash for coding?
Gemini 3 Flash is better for coding, scoring 78.0% on SWE-bench Verified compared to 77.2%. SWE-bench tests real-world software engineering by resolving actual GitHub issues.
Is Claude Sonnet 4.5 cheaper than Gemini 3 Flash?
Yes, Gemini 3 Flash is cheaper. Claude Sonnet 4.5 costs $3.0/1M input and $15.0/1M output tokens. Gemini 3 Flash costs $0.50/1M input and $3.0/1M output tokens.
Which is faster, Claude Sonnet 4.5 or Gemini 3 Flash?
Gemini 3 Flash is faster, generating output at 200 tok/s compared to 67 tok/s. Faster output speed means shorter wait times for API responses.
What benchmarks does the Claude Sonnet 4.5 vs Gemini 3 Flash comparison cover?
This comparison covers 16 benchmarks including Chatbot Arena ELO, MMLU-Pro, HumanEval+, IFEval, MATH, GPQA Diamond, SWE-bench Verified, Output Speed, and more. Metrics span general intelligence, coding, math, reasoning, speed, and cost categories.