What not to paste into ChatGPT

The safest data is the data you never sent. Here is a simple test, a list of what to keep out, and how to still get help.

Quick answer: Do not paste passwords, API keys, client details, confidential contracts, medical information or ID numbers into an AI chatbot. A simple test: would you read it out loud to a stranger on a bus? If not, swap sensitive details for placeholders like "Client A", and check your app's training-data setting.

By The 30-Day AI Habit · Published 2026-10-04 · Updated 2026-10-05

The Stranger Test

Before you paste anything into an AI, ask: "Would I read this out loud to a stranger on a bus?" If the answer is no, do not paste it as it is.

Keep these out of the chat

You can still get help: swap in placeholders

Replace the sensitive bits first, then give the AI the shape of the problem:

"In this chat I'll call my client 'Client A' and my company 'Company B'. Keep using those names."

Check the training setting

Many AI apps can use your conversations to train future models unless you switch that off. The setting is rarely on the front page, and most people have never looked. Find it in each tool you use, and decide on purpose. Even with training switched off, your chats live on someone else's servers for a while, which is why the Stranger Test comes first.

Ask what you have already shared

"What personal or business information have I shared with you in this chat that I might want to delete?"

This is Days 3 and 5 of The 30-Day AI Habit: the Settings Sweep and the Stranger Test. Start the course.

Frequently asked questions

What should you never put into ChatGPT?

Passwords and keys, client or customer details, confidential contracts, medical information, ID numbers and anything you would not read aloud to a stranger.

Does ChatGPT train on my conversations?

Many AI apps can use conversations for training unless you turn that setting off. Check the data controls in each tool you use.

How can I use AI with sensitive documents safely?

Swap real names and figures for placeholders such as Client A and Company B before you paste, and keep the real details in your own files.

Keep reading

Ready to build the habit? The 30-Day AI Habit is a 15-minute-a-day course with one rule and one small task each day. Open the course

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