WhichAI / Compare / Gemini 3.5 Flash vs GPT-5.6 Luna

Gemini 3.5 FlashvsGPT-5.6 Luna

GPT-5.6 Luna scores higher on the October 14, 2026 index. Full context below: price, context window, strengths and honest limits. Verified October 14, 2026.

Gemini 3.5 Flash

GPT-5.6 Luna

Provider

AA index

33.6

37.3

Released

2026-05-19

2026-07-09

Context

1.05M

Price $/1M

$1.5 / $9

$0.2 / $1.2

Access

FREE (most generous free tier) · free API via Google AI Studio

Released July 9, 2026 · API $0.2/$1.2 per 1M tokens

n/a = not published or not yet verified. Scores marked ~ are WhichAI estimates and should not be compared 1:1 with measured scores.

In one line each

Gemini 3.5 Flash: A Flash model that outscores the older 3.1 Pro on the AA index, with the most generous free tier of the big assistants and a free API through Google AI Studio.

GPT-5.6 Luna: The fast, affordable member of the 5.6 series - near-flagship scores at commodity prices; strong default for high-volume API work.

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