Claude Opus 4.5 vs o3 Mini
Side-by-side benchmark comparison across coding, math, reasoning, speed, and pricing.
Claude Opus 4.5 by Anthropic wins on 8 of 15 benchmarks against o3 Mini by OpenAI, 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 4.5 scores 1468 on Chatbot Arena ELO compared to o3 Mini's 1320, while Claude Opus 4.5 scores 89.5% on MMLU-Pro compared to o3 Mini's 78.0%.
Coding: In coding, Claude Opus 4.5 scores 92.0% on HumanEval+ compared to o3 Mini's 87.0%, while Claude Opus 4.5 scores 80.9% on SWE-bench Verified compared to o3 Mini's 50.0%, while Claude Opus 4.5 scores 70.0% on LiveCodeBench compared to o3 Mini's 55.0%.
Math: In math, o3 Mini scores 93.0% on MATH compared to Claude Opus 4.5's 90.0%, while o3 Mini scores 97.0% on GSM8K compared to Claude Opus 4.5's 96.5%.
Reasoning: In reasoning, Claude Opus 4.5 scores 87.0% on GPQA Diamond compared to o3 Mini's 77.0%, while Claude Opus 4.5 scores 57.0% on ARC-AGI compared to o3 Mini's 45.0%.
Context: In context, both score 200K on Context Length.
Pricing Comparison
Claude Opus 4.5 costs $5.0/1M input tokens and $25.0/1M output tokens, while o3 Mini costs $1.1/1M input and $4.4/1M output. o3 Mini is the more affordable option for API usage.
Speed Comparison
Claude Opus 4.5 generates output at 50 tok/s compared to o3 Mini's 100 tok/s, and the time to first token is 1700 ms for Claude Opus 4.5 versus 400 ms for o3 Mini. o3 Mini delivers faster throughput.
Verdict
For developers prioritizing coding and general intelligence, Claude Opus 4.5 has the edge. For those who value math and affordability and speed, o3 Mini is the stronger choice.
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Claude Opus 4.5 vs o3 Mini — FAQ
Which is better, Claude Opus 4.5 or o3 Mini?
Claude Opus 4.5 wins on more benchmarks overall (8 vs 6). However, the best choice depends on your specific needs — each model excels in different areas.
How does Claude Opus 4.5 compare to o3 Mini for coding?
Claude Opus 4.5 is better for coding, scoring 80.9% on SWE-bench Verified compared to 50.0%. SWE-bench tests real-world software engineering by resolving actual GitHub issues.
Is Claude Opus 4.5 cheaper than o3 Mini?
Yes, o3 Mini is cheaper. Claude Opus 4.5 costs $5.0/1M input and $25.0/1M output tokens. o3 Mini costs $1.1/1M input and $4.4/1M output tokens.
Which is faster, Claude Opus 4.5 or o3 Mini?
o3 Mini is faster, generating output at 100 tok/s compared to 50 tok/s. Faster output speed means shorter wait times for API responses.
What benchmarks does the Claude Opus 4.5 vs o3 Mini comparison cover?
This comparison covers 15 benchmarks including Chatbot Arena ELO, MMLU-Pro, HumanEval+, MATH, GPQA Diamond, SWE-bench Verified, Output Speed, LiveCodeBench, and more. Metrics span general intelligence, coding, math, reasoning, speed, and cost categories.