GPT-5.5 (Xhigh) vs GPT-5.6 Terra (Low)
Which is better for the money: GPT-5.5 (Xhigh) by OpenAI or GPT-5.6 Terra (Low) by OpenAI? Intelligence, total benchmark cost, and end-to-end time from Artificial Analysis & other sources, snapshot 2026-10-26.
Trade-off
Verdict
Depends on your budget
GPT-5.5 (Xhigh) scores 10.9 points higher (38.4 vs 27.5) but costs 15× as much to run the benchmark ($5294 vs $350; flagship vs mid-range cost classes). They are not alternatives at one budget: pick GPT-5.5 (Xhigh) when you need intelligence above 27.5, and GPT-5.6 Terra (Low) when 27.5 is enough.
| Metric | GPT-5.5 (Xhigh) | GPT-5.6 Terra (Low) | Difference |
|---|---|---|---|
| Intelligence (higher is better) | 38.4 | 27.5 | −28.4% GPT-5.6 Terra (Low) is 28.4% less intelligent |
| Total AA cost (lower is better) | $5,294.36 | $350.36 | −93.4% GPT-5.6 Terra (Low) is 93.4% cheaper |
| End-to-end time (lower is better) | 82.06s | 5.92s | −92.8% GPT-5.6 Terra (Low) is 92.8% faster |
| Price per 1M tokens (in / out) | $5.00 / $30.0 | $2.00 / $12.0 | |
| Input modalities | Text, Image | Text, Image |
GPT-5.6 Terra (Low) vs GPT-5.5 (Xhigh): 28.4% less intelligence, 93.4% less cost to run the AA benchmark, and 92.8% faster end-to-end.
Today's Pareto frontier
Against the frontier
- GPT-5.5 (Xhigh) is off the frontier: at the same or lower cost, Claude Opus 5.5 (Xhigh, Default Fallback) scores 56.00 for $4057.
- GPT-5.6 Terra (Low) is off the frontier: at the same or lower cost, MiMo-V2.6-Pro scores 46.30 for $207.
GPT-5.5 (Xhigh)GPT-5.6 Terra (Low)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/gpt-5-6-terra-low · Markdown: /api/v1/compare/gpt-5-5/gpt-5-6-terra-low?format=md · llms.txt · agent skill