Which model is better: Claude Opus 5.5 or OpenAI o3?
OpenAI o3 is 50.0% cheaper for input tokens ($2.00 vs. $4.00 per 1M tokens) and $8.00 vs. $20.00 for output tokens (2.0x cost advantage). In terms of operational performance, Claude Opus 5.5 delivers lower response latency at 680ms TTFT (470ms faster than OpenAI o3) with 95 vs. 82 tok/s throughput. Claude Opus 5.5 leads coding evaluations at 89.9% SWE-bench Verified vs. 71.7% for OpenAI o3 and 93.2% vs. 87.7% on GPQA Diamond.
Verified daily via automated API latency tests and official documentation.
Zero-Shot RAG Verified
Verified Performance & Unit Economics Delta (12 Dimensions)
Daily synchronized metrics across token pricing, prompt cache economics, latency, throughput, and 5 capability benchmarks.
Metric / Dimension
Claude Opus 5.5
OpenAI o3
Net Delta / Advantage
Input Cost / 1M Tokens
$4.00
$2.00
OpenAI o3 is 2.0x cheaper
Output Cost / 1M Tokens
$20.00
$8.00
OpenAI o3 (60.0% lower)
Prompt Cache Read / 1M
$0.200
$0.500
Claude Opus 5.5 is 2.5x cheaper
Prompt Cache Write / 1M
$5.00
$2.00
OpenAI o3 is 2.5x cheaper
Context Window (Max Output)
1,024k (128k out)
205k (100k out)
Claude Opus 5.5 (5.0x larger context)
Avg TTFT Response Latency
680ms
1150ms
Claude Opus 5.5 (470ms faster)
Generation Speed (Throughput)
95 tok/s
82 tok/s
Claude Opus 5.5 (+13 tok/s faster)
SWE-bench Verified (Coding)
89.9%
71.7%
Claude Opus 5.5 (+18.2% lead)
GPQA Diamond (PhD STEM)
93.2%
87.7%
Claude Opus 5.5 (+5.5% lead)
MMLU-Pro (Multi-Discipline)
92.1%
89.8%
Claude Opus 5.5 (+2.3% lead)
MATH-500 (Quantitative Logic)
98%
98.6%
OpenAI o3 (+0.6% lead)
Inference Value Score (IVR)
57.8 / 100
60.6 / 100
OpenAI o3 (+2.8 pts)
Interactive Monthly Token Economics & ROI Forecaster
Model production workloads across prompt, completion, and cached context tokens, or switch models on the fly.
Choose Claude Opus 5.5 (Anthropic) for top-ranked frontier intelligence leader for autonomous multi-step agentic coding, repository-scale migrations, and complex scientific reasoning at a 40% lower workload cost than Opus 5 — offering a 1,024k context window, 680ms TTFT, and $4.00/1M input pricing ($0.200/1M cached reads).
OpenAI o3 is cheaper at $2.00/1M input tokens ($8.00/1M output) compared to $4.00/1M input ($20.00/1M output) for Claude Opus 5.5.
Which model has lower TTFT latency and higher tok/s throughput: Claude Opus 5.5 or OpenAI o3?
Claude Opus 5.5 delivers faster first-token latency at 680ms TTFT (95 tok/s throughput) compared to 1150ms TTFT (82 tok/s) for OpenAI o3.
How do Claude Opus 5.5 and OpenAI o3 compare on SWE-bench coding and GPQA Diamond reasoning?
On SWE-bench Verified software engineering, Claude Opus 5.5 scores 89.9% versus 71.7% for OpenAI o3. On GPQA Diamond graduate-level STEM reasoning, Claude Opus 5.5 scores 93.2% versus 87.7% for OpenAI o3 (and 98% vs 98.6% on MATH-500).
When should you choose Claude Opus 5.5?
Choose Claude Opus 5.5 (Anthropic) for top-ranked frontier intelligence leader for autonomous multi-step agentic coding, repository-scale migrations, and complex scientific reasoning at a 40% lower workload cost than Opus 5 — offering a 1,024k context window, 680ms TTFT, and $4.00/1M input pricing ($0.200/1M cached reads).
When should you choose OpenAI o3?
Choose OpenAI o3 (OpenAI) for algorithmic synthesis, mathematical verification, PhD-level scientific research, and multi-step tool planning — offering a 204k context window, 1150ms TTFT, and $2.00/1M input pricing ($0.500/1M cached reads).
