GPT-6.1 Terra (Medium) vs Mercury 2.5
Which is better for the money: GPT-6.1 Terra (Medium) by OpenAI or Mercury 2.5 by Inception? Intelligence, total benchmark cost, and end-to-end time from Artificial Analysis & other sources, snapshot 2026-10-27.
Clear winner
Verdict
Pick GPT-6.1 Terra (Medium)
Mercury 2.5 vs GPT-6.1 Terra (Medium): 70.2% less intelligence, 8.0% more cost to run the AA benchmark, and 40.4% faster end-to-end.
| Metric | GPT-6.1 Terra (Medium) | Mercury 2.5 | Difference |
|---|---|---|---|
| Intelligence (higher is better) | 41.3 | 12.3 | −70.2% Mercury 2.5 is 70.2% less intelligent |
| Total AA cost (lower is better) | $175.20 | $189.17 | +8.0% Mercury 2.5 is 8.0% more expensive |
| End-to-end time (lower is better) | 6.93s | 4.13s | −40.4% Mercury 2.5 is 40.4% faster |
| Price per 1M tokens (in / out) | $1.00 / $5.00 | $0.25 / $0.75 | |
| Input modalities | Text, Image | Text |
Today's Pareto frontier
Against the frontier
- GPT-6.1 Terra (Medium) is on today's frontier: nothing is both smarter and cheaper.
- Mercury 2.5 is off the frontier: at the same or lower cost, GPT-6.1 Terra (Medium) scores 41.30 for $175.
GPT-6.1 Terra (Medium)Mercury 2.5Today'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-6-1-terra-medium/mercury-2-5 · Markdown: /api/v1/compare/gpt-6-1-terra-medium/mercury-2-5?format=md · llms.txt · agent skill