Tag an Image¶

When to Use This Guide¶

Use this guide to give an image an additional name, usually to add a version number or to prepare it for pushing to a registry.

Quick Command

docker tag my-app YOUR_USERNAME/my-app:1.0

Step 1: Tag the Image¶

Point a new name at an existing image.

docker tag my-app YOUR_USERNAME/my-app:1.0

This does not make a copy. It adds a second name for the same image.

Step 2: Confirm¶

docker images

Both my-app and YOUR_USERNAME/my-app will appear, sharing the same IMAGE ID.

Understanding the Format¶

A full image name looks like this:

YOUR_USERNAME/repository:version

If you leave the version off, Docker uses latest by default. Tagging real versions like 1.0 is a good habit, because latest changes meaning over time.

Common Issues¶

No such image

The source image name is wrong. List your images with docker images and copy the name exactly.