GPT-5.5 Instant (June 2026) vs GPT-5.6 Luna (High)
Which is better for the money: GPT-5.5 Instant (June 2026) by OpenAI or GPT-5.6 Luna (High) by OpenAI? Intelligence, total benchmark cost, and end-to-end time from Artificial Analysis & other sources, snapshot 2026-10-27.
Clear winner
Verdict
Pick GPT-5.6 Luna (High)
GPT-5.6 Luna (High) vs GPT-5.5 Instant (June 2026): 23.5% more intelligence, 89.0% less cost to run the AA benchmark, and 0.8% slower end-to-end.
| Metric | GPT-5.5 Instant (June 2026) | GPT-5.6 Luna (High) | Difference |
|---|---|---|---|
| Intelligence (higher is better) | 26.0 | 32.1 | +23.5% GPT-5.6 Luna (High) is 23.5% more intelligent |
| Total AA cost (lower is better) | $986.85 | $108.15 | −89.0% GPT-5.6 Luna (High) is 89.0% cheaper |
| End-to-end time (lower is better) | 16.18s | 16.31s | +0.8% GPT-5.6 Luna (High) is 0.8% slower |
| Price per 1M tokens (in / out) | $5.00 / $30.0 | $0.20 / $1.20 | |
| Input modalities | Text, Image | Text, Image |
Today's Pareto frontier
Against the frontier
- GPT-5.5 Instant (June 2026) is off the frontier: at the same or lower cost, GPT-6.1 Sol (Xhigh) scores 51.00 for $662.
- GPT-5.6 Luna (High) is off the frontier: at the same or lower cost, Claude Haiku 5.5 (High) scores 37.80 for $94.1.
GPT-5.5 Instant (June 2026)GPT-5.6 Luna (High)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-instant-06-26/gpt-5-6-luna-high · Markdown: /api/v1/compare/gpt-5-5-instant-06-26/gpt-5-6-luna-high?format=md · llms.txt · agent skill