I Built Thumbnail Generator with ChatGPT Image 2.0 & GPT 5.5
Build a YouTube, LinkedIn, and X thumbnail generator with ChatGPT Image 2.0 and Codex GPT 5.5. One prompt, 29 minutes, 3 errors. Step by step
I love Claude.
But last week, OpenAI shipped two things I can’t ignore.
Codex with GPT 5.5. And ChatGPT Image 2.0.
Ignoring them breaks two promises I made to you.
Stay on the AI curve
Build with the latest tool on day one
So we’re building an app together. A thumbnail generator for your socials. Powered by ChatGPT Image 2.0.
The thumbnail of this post? Built with the app we’re about to build. One prompt. Under a minute.
What I’m Building With ChatGPT Image 2.0 and GPT 5.5?
I used to do it with Claude Code, but since GPT 5.5 is released, let’s give it a shot to Codex.
We’ll build a thumbnail generator. For YouTube, LinkedIn, and X.
Three modes. Clone someone’s style, pick a preset, or go hybrid with full overrides. Face image in. Title in. Three variants out. Download as PNG.
Here’s the thumbnail generator we’ll build in 29 minutes and 3 errors, using GPT 5.5 and ChatGPT Image 2.0.
How do I know?
Before I started, I told Yevheniya to count the time. Turns out Codex was counting too.
I’m going to show you everything. Step by step.
Building the Thumbnail Generator With Codex GPT 5.5, Step by Step
I used to give you the prompt that 100% works.
Here’s how. I’d start with the initial prompt. Build the app. Hit errors. Fix them. Update the prompt. Then publish. So you don’t see the same errors I did.
Today is different. (You’ll understand why on May 1, 2026, hint.)
I tried to build this with one prompt inside Codex using GPT 5.5.
But I’ll do it with you.
Step by step.
Every error is included.
Let’s start with the initial prompt.