Gemini 3.6 Flash vs GPT-6 Luna
Gemini 3.6 Flash was superseded by Gemini 3.8 Flash. The grades below are the last ones measured, so read them as history rather than as this week's board. See the current roster.
Gemini 3.6 Flash leads overall, C to D. GPT-6 Luna is about 16x cheaper per task. By suite, Gemini 3.6 Flash takes real-world issues (C- to D+) and vibe coding (C+ to F). Take GPT-6 Luna anyway when you want the side that is cheaper per task and faster on real-world issues.Measured
Each agent graded on the same private suites, running headless through its own tools. Advantages are oriented so a win is a win, whichever way the metric runs.
Verdict: GPT-6 Luna vs Gemini 3.6 Flash
Gemini 3.6 Flash leads overall, C to D. By suite: Gemini 3.6 Flash takes real-world issues, C- to D+ (60% vs 50% capability); Gemini 3.6 Flash takes vibe coding, C+ to F (72% vs 33% capability). Only GPT-6 Luna has run spec planning. Gemini 3.6 Flash used 12.6% of Google AI Pro's weekly limit per pass, $0.039 per task at the listed price. GPT-6 Luna used 1% of ChatGPT Plus's weekly limit per pass, $0.002 per task at the listed price; at the ~$100 tier the board defaults to that is an estimated ~0.2% of ChatGPT Pro 5x's weekly limit (est, about $0.002 per task). Per task, GPT-6 Luna is about 16x cheaper ($0.002 vs $0.039). GPT-6 Luna is faster on real-world issues: a median task takes 1m 0s against 2m 17s. Both finished every task on it. Reasons to pick GPT-6 Luna anyway: it is cheaper per task ($0.002 vs $0.039) and it is faster on real-world issues (1m 0s vs 2m 17s median).
No change since W32.
| Dimension | Gemini 3.6 Flash | GPT-6 Luna | Advantage |
|---|---|---|---|
| Capability | 60% | 50% | +10% (Gemini 3.6 Flash leads) |
| Median task time | 2m 17s | 1m 0s | 1m 17s faster (GPT-6 Luna leads) |
| Approx. task cost | $0.039 / task | $0.003 / task | $0.036 / task lower (GPT-6 Luna leads) |
Gemini 3.6 Flash: 12.6% of Google AI Pro (about 72.1% / 5h, 12.6% / 1w) per run. Its weekly limit holds 6 of the week's 33.6 5h windows. GPT-6 Luna: 1.0% of ChatGPT Plus (1.0% / 5h, 1.0% / 1w) per run. Its weekly limit holds about 6 of the week's 33.6 5h windows. Each figure is a share of that agent's own plan, so there is no delta to draw.
Only GPT-6 Luna has run this suite, so there is no head-to-head yet.
| Dimension | Gemini 3.6 Flash | GPT-6 Luna | Advantage |
|---|---|---|---|
| Capability | 72% | 33% | +39% (Gemini 3.6 Flash leads) |
| Median task time | 1m 54s | 1m 37s | 17s faster (GPT-6 Luna leads) |
| Approx. task cost | $0.038 / task | not measured | - |
Gemini 3.6 Flash: 0.8% of Google AI Pro (4.9% / 5h, 0.8% / 1w) per good solve. Its weekly limit holds 6 of the week's 33.6 5h windows. GPT-6 Luna: under 1% of ChatGPT Plus (0.4% / 5h) per good solve. Its weekly limit holds about 6 of the week's 33.6 5h windows. Each figure is a share of that agent's own plan, so there is no delta to draw.
Grades and deltas are comparable only within a suite version. See methodology.
Frequently asked questions
Which is better for coding, Gemini 3.6 Flash or GPT-6 Luna?
Gemini 3.6 Flash clears higher: tier 4 of 5 versus tier 2 for GPT-6 Luna on real-world@v3, our private suite of real-world coding problems. Latest measurement 2026-08-10.
Which is cheaper per task, Gemini 3.6 Flash or GPT-6 Luna?
Gemini 3.6 Flash used 12.6% of Google AI Pro's weekly limit per pass, $0.039 per task at the listed price. GPT-6 Luna used 1% of ChatGPT Plus's weekly limit per pass, $0.002 per task at the listed price; at the ~$100 tier the board defaults to that is an estimated ~0.2% of ChatGPT Pro 5x's weekly limit (est, about $0.002 per task). Per task, GPT-6 Luna is about 16x cheaper ($0.002 vs $0.039).