Compare / head-to-head
GPT-5.4 nanovsGPT-5.6 Luna
GPT-5.6 Luna leads 6 of 6 shared benchmarks. GPT-5.6 Luna is marginally cheaper per token. GPT-5.6 Luna has the larger context window (1.1M tokens).
Benchmarks from cited public sources; pricing from official pages; status from official provider feeds.
Shared benchmarks
0 – 6
GPT-5.6 Luna leads
Cheaper per token
GPT-5.6 Luna
1x cheaper, input + output
Larger context
GPT-5.6 Luna
1.1M tokens
Provider uptime (30d)
94.8387%
OpenAI
GPT-5.4 nano
OpenAI · released 2026-03-17
textvision
GPT-5.6 Luna
OpenAI · released 2026-07-09
textvision
Quality
Benchmark matrix
6 shared · 3 only GPT-5.4 nano · 1 only GPT-5.6 Luna| Benchmark | GPT-5.4 nano | GPT-5.6 Luna | Δ | Edge |
|---|---|---|---|---|
| Reported by both · 6 | ||||
| GPQA Diamond | 82.8% ↗ | 92.3% ↗ | -9.5 pt | GPT-5.6 Luna |
| FrontierMath Tier 4 v2 (Epoch AI run) | 12.2% ↗epoch | 61% ↗epoch | -48.8 pt | GPT-5.6 Luna |
| FrontierMath Tiers 1-3 v2 (Epoch AI run) | 44.9% ↗epoch | 82.1% ↗epoch | -37.2 pt | GPT-5.6 Luna |
| OTIS Mock AIME 2024-2025 (Epoch AI run) | 87.8% ↗epoch | 98.3% ↗epoch | -10.5 pt | GPT-5.6 Luna |
| SimpleQA Verified | 11.7% ↗epoch | 41% ↗epoch | -29.3 pt | GPT-5.6 Luna |
| SWE-Bench Pro | 52.4% ↗ | 62.7% ↗ | -10.3 pt | GPT-5.6 Luna |
| Only GPT-5.4 nano reports · 3 | ||||
| OSWorld-Verified | 39% ↗ | not reported | — | — |
| Terminal-Bench 2.0 | 46.3% ↗ | not reported | — | — |
| Toolathlon | 35.5% ↗ | not reported | — | — |
| Only GPT-5.6 Luna reports · 1 | ||||
| DeepSWE v1.1 | not reported | 67.2% ↗ | — | — |
Scores tagged "epoch" or "matharena" are independent runs, used only where the lab has not published its own; ⚠ marks rows MathArena flags as released after the competition. Higher is better on every row. Δ is GPT-5.4 nano minus GPT-5.6 Luna in the benchmark's own unit. "Not reported" means the lab has not published that figure; it is not a zero. ↗ opens the source.
Specs & pricing
Side by side
Official pricing pages and model cards| Spec | GPT-5.4 nano | GPT-5.6 Luna | Edge |
|---|---|---|---|
| Context window | 400K tokens | 1.1M tokens | GPT-5.6 Luna |
| Max output | 128K tokens | 128K tokens | Tie |
| Input price / 1M | $0.2 ↗ | $0.2 ↗ | Tie |
| Output price / 1M | $1.25 ↗ | $1.2 ↗ | GPT-5.6 Luna |
| Cached input / 1M | $0.02 ↗ | $0.02 ↗ | Tie |
| Input + output / 1M Lower is cheaper. List prices; batch, tool and regional fees excluded. | $1.45 | $1.4 | GPT-5.6 Luna |
| Modalities | text · vision | text · vision | Tie |
| Released | 2026-03-17 | 2026-07-09 | — |
| Cited benchmark scores | 10 | 8 | — |
Reliability
OpenAI status
Last 60 days · refreshed daily on this page · live on /statusMore matchups
GPT-5.4 nano vs …
Models sharing the most benchmarksMore matchups
GPT-5.6 Luna vs …
Models sharing the most benchmarksBuilt by Respan
Which one wins on your data?
Public benchmarks are a starting point. Run GPT-5.4 nano and GPT-5.6 Luna on your own prompts with Respan evals, or route to either through one gateway key with automatic failover.