ChatGPT vs. Codex: what's the difference?
In one line
ChatGPT vs. Codex: what’s the difference?
ChatGPT helps you think things through; Codex helps you build. Here’s how to pick.
The big picture
Illustration (may look a little different from the real screen)
Follow along
“They’re both AIs that help when I ask in plain words. So which one should I use?”
It’s easiest to choose based on what you want to get done.
Same AI, different starting point
★ Compare them ★
Use ChatGPT to sort out your thinking
Use it to learn a new idea, plan a trip, or tidy up meeting notes. Go back and forth in the chat and shape the result little by little.
Use Codex to build a small tool
Use it to understand and change code, or to build websites and automation scripts. When it’s connected to your workspace, it can look through files, change code, and check the results as it works.
The two overlap in places. Think of this split as a guide for choosing where to start.
Try asking Codex like this
Your first practice project is a “web page for logging books you’ve read.” Instead of describing a big app, ask for one specific feature you need.
Illustration (may look a little different from the real screen)
Make a web page for logging books I've read.
Sample replyHere's how I'll go about it:
○ Lay out the page
○ Create the files
○ Check the result
Make a web page for logging books I've read.
Sample replyHere's how I'll go about it:
○ Lay out the page
○ Create the files
○ Check the result
Copy this to get started
Your request turns into a small, real result
When it’s done, look at the files it made and the page itself. The important part is clicking around yourself to check that the feature actually works.
🖍️ About the picture: an example result for learning. Shows index.html and styles.css files, and a preview of a “My Reading Log” web page with a list of books.
Yes, you can start by describing what you want in plain words. Picking up a little about files, folders, and how to run things makes it much easier to understand and check the results.
Can I start for free?
Start small and practice first. What you can use, and how much, depends on your plan. Also keep in mind that using Codex through your ChatGPT account and using it with an API key are billed differently.
Show the plan comparison
| Plan | Listed price |
|---|---|
| Free | $0 |
| Go | $8/month |
| Plus | $20/month |
| Pro | $100 / $200 / $500 per month |
| Business | $20 per user/month billed annually $25 billed monthly · 2+ users |
| Enterprise · Edu | Contact sales |
API key usage is billed separately from your subscription. Prices can vary by region, taxes, how you pay, and policy changes, so check the official prices and current limits before paying. This table isn’t updated in real time.
Official pricing and terms ↗A prompt you can copy
Copy the prompt below, replace the parts in square brackets with your own situation, and paste it into ChatGPT or Codex.
Find ways to cut repetitive work
Where people get stuck
Quick check: I want a program that merges the CSV files I download every week. Which tool should I try first?
Answer: “Codex”
With Codex you can build the program and check the results of running it.
Official sources
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