AnthropicClaude Opus 5VSGoogleGemini 3 Flash
Our Take
We recommend Claude Opus 5 if you need peak intelligence for complex complex codebases, multi-file repositories, and architectural planning, or the 8.9x cheaper Gemini 3 Flash if your workflow is limited to multi-file code and clearly defined tasks. While Claude Opus 5 holds a major reasoning advantage, Gemini 3 Flash is optimized for high-volume budget pipelines. Choose Claude Opus 5 for architectural codebase planning, or Gemini 3 Flash to maximize your budget for basic scripts.
▶WHY?
Benchmark Calculations & Evidence:
Coding Evaluation: Claude Opus 5 was evaluated on SWE-bench Pro (scoring 79.2%), while Gemini 3 Flash was evaluated on SWE-bench Verified (scoring 78%).
Reasoning Accuracy: Both models were evaluated on the GPQA Diamond benchmark. Claude Opus 5 scored 93.7%, while Gemini 3 Flash scored 90.4%.
Cost Efficiency: Gemini 3 Flash pricing ($0.5/M input, $3/M output) is 8.9x cheaper than Claude Opus 5 ($5/M input, $25/M output).
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Benchmarks & Scores
Coding (swe-bench-pro)
79.2%complex codebases, multi-file repositories, and architectural planning
Reasoning (gpqa-diamond)Winner (+3.3%)
93.7%graduate-level science QA
Cost & Context
Cost (per 1M tokens)
$10.00Input: $5.00 | Output: $25.00Context Window
1.05M tokensBenchmarks & Scores
Coding (swe-bench-verified)
78%multi-file code and clearly defined tasks
Reasoning (gpqa-diamond)
90.4%graduate-level science QA
Cost & Context
Cost (per 1M tokens)8.9x cheaper
$1.13Input: $0.50 | Output: $3.00Context Window
1.05M tokensFrequently Asked Questions about Claude Opus 5 vs Gemini 3 Flash
Gemini 3 Flash is cheaper than Claude Opus 5. Gemini 3 Flash has a blended cost of $1.13/1M tokens, which is about 8.9x cheaper than Claude Opus 5 at $10.00/1M tokens.
For coding tasks, Claude Opus 5 scores 79.2% on swe-bench-pro (complex codebases, multi-file repositories, and architectural planning), while Gemini 3 Flash scores 78% on swe-bench-verified (multi-file code and clearly defined tasks).
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