Compare / head-to-head
Gemini 3.8 Flashvs
GPT-6 Luna
Gemini 3.8 Flash leads 1 of 1 shared benchmark. GPT-6 Luna is 7.5x cheaper per token. GPT-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
1 – 0
Gemini 3.8 Flash leads
Cheaper per token
GPT-6 Luna
7.5x cheaper, input + output
Larger context
GPT-6 Luna
1.1M tokens
Providers
2 providers
Google · OpenAI
Gemini 3.8 Flash
Google · released 2026-09-02
textvisionaudio
GPT-6 Luna
OpenAI · released 2026-09-22
textvision
Quality
Benchmark matrix
1 shared · 14 only Gemini 3.8 Flash · 0 only GPT-6 Luna| Benchmark | Gemini 3.8 Flash | GPT-6 Luna | Δ | Edge |
|---|---|---|---|---|
| Reported by both · 1 | ||||
| DeepSWE v1.1 | 73.7% ↗ | 66.6% ↗ | +7.1 pt | Gemini 3.8 Flash |
| Only Gemini 3.8 Flash reports · 14 | ||||
| GPQA Diamond | 95.3% ↗ | not reported | — | — |
| CharXiv Reasoning (no tools) | 86.2% ↗ | not reported | — | — |
| FrontierMath Tier 4 v2 (Epoch AI run) | 22% ↗epoch | not reported | — | — |
| FrontierMath Tiers 1-3 v2 (Epoch AI run) | 68.4% ↗epoch | not reported | — | — |
| GDPVal-AA v2 | 1545 ↗ | not reported | — | — |
| Harvey's Legal Agent Benchmark | 10% ↗ | not reported | — | — |
| HLE-Verified | 54.9% ↗ | not reported | — | — |
| LABBench2 | 86.2% ↗ | not reported | — | — |
| OSWorld-2.0 | 59% ↗ | not reported | — | — |
| OTIS Mock AIME 2024-2025 (Epoch AI run) | 98.9% ↗epoch | not reported | — | — |
| SimpleQA Verified | 69.7% ↗epoch | not reported | — | — |
| Terminal-bench 2.1 | 89.4% ↗ | not reported | — | — |
| Terminal-bench 4.0 | 19.1% ↗ | not reported | — | — |
| Vals Finance Agent v2 | 61.4% ↗ | not reported | — | — |
| Only GPT-6 Luna reports · 0 | ||||
| GPT-6 Luna reports nothing Gemini 3.8 Flash does not. | ||||
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 Gemini 3.8 Flash minus GPT-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 | Gemini 3.8 Flash | GPT-6 Luna | Edge |
|---|---|---|---|
| Context window | 1.0M tokens | 1.1M tokens | GPT-6 Luna |
| Max output | 66K tokens | 128K tokens | GPT-6 Luna |
| Input price / 1M | $0.75 ↗ | $0.1 ↗ | GPT-6 Luna |
| Output price / 1M | $3.75 ↗ | $0.5 ↗ | GPT-6 Luna |
| Cached input / 1M | $0.075 ↗ | $0.01 ↗ | GPT-6 Luna |
| Input + output / 1M Lower is cheaper. List prices; batch, tool and regional fees excluded. | $4.5 | $0.6 | GPT-6 Luna |
| Modalities | text · vision · audio | text · vision | Gemini 3.8 Flash |
| Released | 2026-09-02 | 2026-09-22 | — |
| Cited benchmark scores | 16 | 1 | — |
Reliability
Provider status
Live from /statusMore matchups
Gemini 3.8 Flash vs …
Models sharing the most benchmarksMore matchups
GPT-6 Luna vs …
Models sharing the most benchmarksBuilt by Respan
Which one wins on your data?
Public benchmarks are a starting point. Run Gemini 3.8 Flash and GPT-6 Luna on your own prompts with Respan evals, or route to either through one gateway key with automatic failover.