Skip to main content

GPT Image 1.5 vs Nano Banana Pro (2026): Which Wins

By Johnathan Kwok · VibeDex Research

TL;DR

GPT Image 1.5 edges ahead of Nano Banana Pro in the current public Sonnet leaderboard. GPT Image 1.5 scores 4.015 at $0.133/image. Nano Banana Pro scores 3.959 at $0.138/image. The 0.056-point gap is small, but GPT Image 1.5 is ahead on both score and price.

Current Sonnet Comparison

The previous version of this comparison was based on the retired Gemini dataset. The current public leaderboard uses Claude Sonnet 4.6 across the 50-prompt image set, so the article now uses the same numbers as the leaderboard and Atlas.

#ModelSonnet ScoreCost/ImageTier
5GPT Image 1.54.01$0.133Premium
8Nano Banana Pro3.96$0.138Premium

Which Should You Use?

GPT Image 1.5

Strengths

  • +Slightly higher current public Sonnet score
  • +Slightly lower listed price
  • +Strong pick when OpenAI workflow compatibility matters

Limitations

  • No longer the clear leaderboard leader
  • Only 0.056 points ahead of Nano Banana Pro

Nano Banana Pro

Strengths

  • +Nearly identical current Sonnet score
  • +Strong premium alternative to GPT Image 1.5
  • +Useful when Google model access or style is preferred

Limitations

  • Slightly more expensive in the current cost table
  • Sits just behind GPT Image 1.5 in the public ranking

Related Vibedex Benchmarks

Methodology: Rankings and scores in this article align to VibeDex's current Sonnet 4.6 blind benchmark: 50 prompts, 3 passes, and 150 judgments per model across visual fidelity, physics, subject integrity, and instruction adherence. See our full methodology

FAQ

Is GPT Image 1.5 better than Nano Banana Pro now?

In the current Sonnet benchmark, GPT Image 1.5 is ahead by 0.056 points: 4.015 versus 3.959.

Which is cheaper?

GPT Image 1.5 is slightly cheaper at $0.133/image versus $0.138/image for Nano Banana Pro.

Does this article use retired Gemini benchmark scores?

No. This rewrite uses current Sonnet leaderboard scores only.

See how every model stacks up

The Vibedex leaderboard ranks 18 image models on a 50-prompt blind benchmark, judged by Claude Sonnet 4.6 across visual fidelity, physics, subject integrity, and instruction adherence.

See the leaderboard