GPT-5.5 (Medium) vs GPT-5.6 Terra (Xhigh)
Which is better for the money: GPT-5.5 (Medium) by OpenAI or GPT-5.6 Terra (Xhigh) by OpenAI? Intelligence, total benchmark cost, and end-to-end time from Artificial Analysis & other sources, snapshot 2026-10-26.
Clear winner
Verdict
Pick GPT-5.6 Terra (Xhigh)
GPT-5.6 Terra (Xhigh) vs GPT-5.5 (Medium): 12.4% more intelligence, 43.4% less cost to run the AA benchmark, and 153.7% slower end-to-end.
| Metric | GPT-5.5 (Medium) | GPT-5.6 Terra (Xhigh) | Difference |
|---|---|---|---|
| Intelligence (higher is better) | 33.8 | 38.0 | +12.4% GPT-5.6 Terra (Xhigh) is 12.4% more intelligent |
| Total AA cost (lower is better) | $2,095.12 | $1,186.77 | −43.4% GPT-5.6 Terra (Xhigh) is 43.4% cheaper |
| End-to-end time (lower is better) | 13.28s | 33.69s | +153.7% GPT-5.6 Terra (Xhigh) is 153.7% slower |
| Price per 1M tokens (in / out) | $5.00 / $30.0 | $2.00 / $12.0 | |
| Input modalities | Text, Image | Text, Image |
Today's Pareto frontier
Against the frontier
- GPT-5.5 (Medium) is off the frontier: at the same or lower cost, GPT-6.1 Sol (Max) scores 51.80 for $1082.
- GPT-5.6 Terra (Xhigh) is off the frontier: at the same or lower cost, GPT-6.1 Sol (Max) scores 51.80 for $1082.
GPT-5.5 (Medium)GPT-5.6 Terra (Xhigh)Today's Pareto frontierEvery other model
Matchup
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Accept: text/markdown or ?format=md returns this page as Markdown. JSON: /api/v1/compare/gpt-5-5-medium/gpt-5-6-terra-xhigh · Markdown: /api/v1/compare/gpt-5-5-medium/gpt-5-6-terra-xhigh?format=md · llms.txt · agent skill