Codex (OpenAI) vs Nano Banana 2 (Gemini 3.1 Flash Image)

Nano Banana 2 (Gemini 3.1 Flash Image) edges out Codex (OpenAI) by 0.6 points (8.9 vs 8.3) -- a A-tier vs A-tier split that's narrow but real. Not a blowout; both belong on a shortlist. The score gap shows up most clearly in the categories that matter for Nano Banana 2 (Gemini 3.1 Flash Image)'s strengths, so if those categories are your priority, the lead translates.

Pricing-wise, both tools have a free tier (Codex (OpenAI) starts $0, Nano Banana 2 (Gemini 3.1 Flash Image) starts $0), so you can test either without committing. Compare what each free tier actually unlocks -- usage caps, model access, and feature gates differ a lot more than the headline price suggests, especially as both vendors have tightened limits in 2026.

By use case: pick Codex (OpenAI) when developers already paying for chatgpt plus who want a coding agent at no extra cost. Pick Nano Banana 2 (Gemini 3.1 Flash Image) when designers, marketers, and content creators who need readable text in images (social posts, ad creative, book covers, infographics, event flyers) and who are already using or willing to pay for gemini. The two tools aren't fighting for the same person -- they're aiming at adjacent jobs that occasionally overlap. If you're squarely in Nano Banana 2 (Gemini 3.1 Flash Image)'s lane, the tier-list ranking and the use-case fit point the same direction; if you're in Codex (OpenAI)'s lane, the score gap matters less than the fit.

Bottom line: Nano Banana 2 (Gemini 3.1 Flash Image) is the safer default for most readers, but Codex (OpenAI) is competitive enough that the tie-breaker is your specific workload, not the spec sheet.