GPT 5.5 InstantvsGPT 5.6 Luna Xhigh
GPT 5.5 Instant leads the overall Podium Score by 1.0 points (74.0 vs 73.0).Category wins: GPT 5.5 Instant 0 — 0 GPT 5.6 Luna Xhigh.GPT 5.5 Instant is the cheaper pick ($10/M vs $10/M per 1M output tokens). GPT 5.5 Instant is faster (50 t/s vs 50 t/s).
| Metric | GPT 5.5 Instant | GPT 5.6 Luna Xhigh |
|---|---|---|
| Podium Score | 74.0 ▲ | 73.0 |
| Arena Elo | — | — |
| Intelligence Index | — | — |
| Coding | — | — |
| Math | — | — |
| Reasoning | — | — |
| Agentic | — | — |
| Knowledge | — | — |
| Multimodal | — | — |
| Long-context | — | — |
| Output speed | 50 t/s | 50 t/s |
| Output price | $10/M | $10/M |
| Context window | 128K | 128K |
Scores aggregated from five leaderboards on 2026-08-05. See Methodology. More head-to-heads: GPT 5.5 Instant vs Claude Mythos Preview · GPT 5.5 Instant vs Claude Fable 5 · GPT 5.5 Instant vs Kimi K3 · GPT 5.5 Instant vs Claude Opus 5