Creating a custom emoji takes two minutes and requires workspace admin permission

To create a custom emoji in Slack, you need admin access to your workspace. If you have that permission, go to your workspace name in the top left, select "Settings & administration," then "Manage apps." From there, click "Custom Emoji" and choose "Add Custom Emoji." Upload an image file (PNG, GIF, JPG, or BMP), name it, and save. The emoji appears in your workspace's emoji picker immediately and is available to all members.

The process is the same whether you are on desktop or mobile, though uploading files is easier on a computer. If you do not have admin access, ask your workspace owner or an admin to create the emoji for you, or request that they give you the permission to do it yourself.

Key Takeaways

  • You must have admin or owner status in your Slack workspace to create custom emoji — regular members cannot do this.
  • Custom emoji files must be PNG, GIF, JPG, or BMP format and should be square images for best results.
  • Once created, a custom emoji is available to everyone in your workspace and appears in the emoji picker alongside standard emoji.
  • You can create as many custom emoji as you want, and there is no limit on how many your workspace can have.

Image requirements and file size limits

Slack accepts PNG, GIF, JPG, and BMP files for custom emoji. The image should be square (the same width and height) so it displays correctly in messages and reactions. A 128 x 128 pixel image works well, though Slack will resize larger images automatically.

File size must be under 64 KB. If your image is too large, compress it before uploading. Most image editing tools or free online compressors can reduce file size without losing much quality. Animated GIFs are allowed and will play when someone uses the emoji in a reaction or message.

Where to find the Custom Emoji menu

On desktop, click your workspace name in the top left corner. A dropdown menu appears. Select "Settings & administration" and then "Manage apps." You will see a sidebar with different options — click "Custom Emoji" to see all emoji your workspace has created.

From the Custom Emoji page, click the blue "Add Custom Emoji" button in the top right. This opens the upload form. On mobile, the path is the same: workspace name, Settings & administration, Manage apps, Custom Emoji, then the add button.

Naming your emoji so people can find it

When you upload an image, Slack asks you to name the emoji. Use a short, descriptive name without spaces — Slack converts spaces to underscores automatically. Good names are thumbsup_custom, team_mascot, or coffee_break. Avoid names that are too long or hard to remember, since people type the name to search for the emoji in the picker.

You can also add aliases, which are alternate names for the same emoji. If you create an emoji called laughing_face, you could add lol and haha as aliases. Then anyone can type any of those three names to find it. Aliases are useful when your emoji has multiple meanings or common nicknames.

Making emoji from photos or screenshots

You do not need design software to create a custom emoji. A simple photo, screenshot, or image from the internet works fine as long as it is square and under 64 KB. Crop the image to be square using your phone's photo editor or a free tool like Canva, Pixlr, or Photoshop Express.

Many teams create emoji from photos of their office, team members, or inside jokes. Screenshots of text, logos, or memes are also common. The only rule is that the image must be your own or you must have permission to use it — Slack does not police this, but using someone else's copyrighted image could create problems for your workspace.

Editing or deleting emoji you have created

To edit an emoji after you create it, go back to the Custom Emoji page, find the emoji in the list, and click the pencil icon next to it. You can change the name, add or remove aliases, or upload a new image. The changes take effect immediately for everyone in the workspace.

To delete an emoji, click the trash icon next to it on the Custom Emoji page. Deleted emoji no longer appear in the picker, but any messages or reactions that used that emoji will show a broken image. There is no way to recover a deleted emoji, so make sure you want to remove it before you confirm.

Troubleshooting common problems

If the upload fails, check that your file is in one of the allowed formats (PNG, GIF, JPG, BMP) and is under 64 KB. If the image is too large, use an online image compressor or resize it in your phone's photo editor. If you get a permission error, you do not have admin access — ask your workspace owner to create the emoji or grant you admin rights.

If the emoji looks blurry or stretched after upload, the original image was not square. Crop it so the width and height are equal, then upload again. If the emoji name is already taken, Slack will tell you — choose a different name or add a number or underscore to make it unique.

Frequently Asked Questions

Can regular members create custom emoji or only admins?

Only workspace owners and admins can create custom emoji. If you are a regular member and want to create one, ask your workspace owner or an admin to do it for you, or request that they give you admin permission.

What happens to messages that used an emoji I deleted?

The emoji will show as a broken image in any message or reaction where it was used. The message itself stays, but the emoji no longer displays. This is why you should be careful before deleting an emoji that people have already used.

Can I use an emoji from another workspace in my workspace?

No. Custom emoji are specific to each workspace and cannot be transferred or shared between workspaces. If you want the same emoji in multiple workspaces, you have to upload it separately to each one.

Is there a limit to how many custom emoji I can create?

Slack does not set a hard limit on the number of custom emoji a workspace can have. However, very large numbers of emoji can make the emoji picker slower to load. Most workspaces have between 50 and 500 custom emoji without performance issues.

Can I make an emoji that is animated?

Yes. Upload an animated GIF instead of a static image. The GIF will play when someone uses the emoji in a reaction or message. The file must still be under 64 KB and should be square for best results.