Claude Opus 4 vs Gemini 2.5 Flash

Side-by-side benchmark comparison across coding, math, reasoning, speed, and pricing.

Claude Opus 4 by Anthropic wins on 11 of 17 benchmarks against Gemini 2.5 Flash by Google, 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, Claude Opus 4 scores 1375 on Chatbot Arena ELO compared to Gemini 2.5 Flash's 1320, while Claude Opus 4 scores 83.0% on MMLU-Pro compared to Gemini 2.5 Flash's 73.0%.

Coding: In coding, Claude Opus 4 scores 90.0% on HumanEval+ compared to Gemini 2.5 Flash's 82.0%, while Claude Opus 4 scores 72.5% on SWE-bench Verified compared to Gemini 2.5 Flash's 38.0%, while Claude Opus 4 scores 60.0% on LiveCodeBench compared to Gemini 2.5 Flash's 42.0%, while Claude Opus 4 scores 1171 on Design Arena ELO compared to Gemini 2.5 Flash's 1056, while Claude Opus 4 scores 1177 on Website Arena ELO compared to Gemini 2.5 Flash's 1086.

Math: In math, Claude Opus 4 scores 86.0% on MATH compared to Gemini 2.5 Flash's 76.0%, while Claude Opus 4 scores 95.0% on GSM8K compared to Gemini 2.5 Flash's 91.0%.

Reasoning: In reasoning, Claude Opus 4 scores 79.6% on GPQA Diamond compared to Gemini 2.5 Flash's 72.7%, while Claude Opus 4 scores 45.0% on ARC-AGI compared to Gemini 2.5 Flash's 25.0%.

Context: In context, Gemini 2.5 Flash scores 1.0M on Context Length compared to Claude Opus 4's 200K.

Pricing Comparison

Claude Opus 4 costs $15.0/1M input tokens and $75.0/1M output tokens, while Gemini 2.5 Flash costs $0.30/1M input and $2.5/1M output. Gemini 2.5 Flash is the more affordable option for API usage.

Speed Comparison

Claude Opus 4 generates output at 50 tok/s compared to Gemini 2.5 Flash's 251 tok/s, and the time to first token is 550 ms for Claude Opus 4 versus 410 ms for Gemini 2.5 Flash. Gemini 2.5 Flash delivers faster throughput.

Verdict

For developers prioritizing coding and general intelligence and math, Claude Opus 4 has the edge. For those who value affordability and speed, Gemini 2.5 Flash is the stronger choice.

Claude Opus 4 vs Gemini 2.5 Flash — FAQ

Which is better, Claude Opus 4 or Gemini 2.5 Flash?

Claude Opus 4 wins on more benchmarks overall (11 vs 6). However, the best choice depends on your specific needs — each model excels in different areas.

How does Claude Opus 4 compare to Gemini 2.5 Flash for coding?

Claude Opus 4 is better for coding, scoring 72.5% on SWE-bench Verified compared to 38.0%. SWE-bench tests real-world software engineering by resolving actual GitHub issues.

Is Claude Opus 4 cheaper than Gemini 2.5 Flash?

Yes, Gemini 2.5 Flash is cheaper. Claude Opus 4 costs $15.0/1M input and $75.0/1M output tokens. Gemini 2.5 Flash costs $0.30/1M input and $2.5/1M output tokens.

Which is faster, Claude Opus 4 or Gemini 2.5 Flash?

Gemini 2.5 Flash is faster, generating output at 251 tok/s compared to 50 tok/s. Faster output speed means shorter wait times for API responses.

What benchmarks does the Claude Opus 4 vs Gemini 2.5 Flash comparison cover?

This comparison covers 17 benchmarks including Chatbot Arena ELO, MMLU-Pro, HumanEval+, MATH, SWE-bench Verified, GPQA Diamond, Output Speed, Time to First Token, and more. Metrics span general intelligence, coding, math, reasoning, speed, and cost categories.