October 13, 2026

Set ChatGPT custom instructions once

Settings > Personalization, or Customize ChatGPT. Keep it short, and leave secrets out.

• AI tools
• Easy · 3 min
• ChatGPT on the web, desktop, iOS, and Android
• Fix: set ChatGPT custom instructions
• ChatGPT
• Cheat sheet

How to do it

1. 01

   Open ChatGPT Settings.

2. 02

   Open Personalization, or Customize ChatGPT if that is the label.

3. 03

   Turn customization on and write how you want answers: short, steps first, say when unsure. Do not put your address, workplace secrets, or passwords in the box.

4. 04

   Save. Start a new chat and check that the shape of the answer changed.

Temporary chats do not use these instructions unless you turn personalization on for that chat. A Project uses the project instructions instead.

Updates apply to later replies. They do not rewrite old conversations.