Side-by-side comparison of pricing, 12 benchmarks, and generation speed.
| Metric | Claude 3 Opus | o3-pro |
|---|---|---|
| Input ($/M tokens) | $15 | $20 |
| Output ($/M tokens) | $75 | $80 |
Verdict. Claude 3 Opus and o3-pro split the benchmark comparison evenly at 1–1. The tiebreaker here is price, speed, and what you actually run them on.
Pricing. Both models sit in the premium bracket for output-token pricing. At 0.9× the per-million-token cost, Claude 3 Opus is meaningfully cheaper if your traffic is output-heavy (long completions, document generation, agent loops). Claude 3 Opus makes more sense when output volume is low and absolute reasoning quality justifies the premium.
Strengths. Claude 3 Opus is strongest on Coding Index (19.5), Intelligence Index (11.8). o3-pro leads on Intelligence Index (33.3).
Speed. Speed data is incomplete for this pair; benchmark and price should decide.
Provider. Anthropic and OpenAI sell to overlapping but distinct developer audiences: Anthropic tends to ship frontier reasoning models with premium positioning, while OpenAI often prices more aggressively. Your existing vendor relationships, billing, and SLA preferences may matter as much as the raw numbers above.
Workload cost. Workload scenarios (per million requests at 30M input + 15M output tokens): Claude 3 Opus costs $1575.00 ($18900/year); o3-pro costs $1800.00 ($21600/year). At a smaller 5M-input/2M-output scale (single-developer tool or prototype): Claude 3 Opus ≈ $225.00/run, o3-pro ≈ $260.00/run. At agent/realtime scale (200M input / 100M output per million requests): Claude 3 Opus ≈ $10500/run, o3-pro ≈ $12000/run. Claude 3 Opus becomes more attractive at higher volume — the absolute per-token pricing difference compounds when you ship at scale.
Recommendation. Both models have legitimate use cases — the right answer depends on whether you are optimizing for benchmark ceiling, latency, or unit cost. Start with the cheaper / faster model, evaluate against your specific task, and only switch if the upgrade shows a meaningful lift.
Head-to-head deltas
Data from Artificial Analysis API — 12 benchmarks
Claude 3 Opus is cheaper overall. Its blended price (3:1 input/output ratio) is $30.00/M tokens vs $35.00/M for o3-pro.
It's a tie — both models win 1 benchmarks each across 12 evaluated categories. See the detailed benchmark chart above for per-category results.
Both models have comparable generation speeds.
Choose based on your priorities: Claude 3 Opus for lower cost, both perform similarly on benchmarks, and both have comparable speed. For latency-sensitive apps, check the TTFT comparison above.