Creating a custom emoji takes two minutes and requires no special permissions

Custom emoji in Slack are small images you upload to your workspace that appear alongside standard emoji in the picker. You create them through your workspace settings, upload an image file, give it a name, and it becomes available to everyone in that workspace when ready. The process works the same way on desktop and mobile, though uploading is easier on a computer.

You do not need to be a workspace admin to create emoji — any member can do it unless your admin has specifically restricted the permission. The image can be a PNG, JPG, GIF, or even an animated GIF, and Slack will automatically resize it to fit the emoji grid.

Key Takeaways

  • Custom emoji are uploaded through Workspace Settings, not through a chat message or menu.
  • Any workspace member can create emoji unless an admin has turned off that permission.
  • Image files should be at least 128 pixels square, though Slack accepts and resizes smaller images.
  • Once uploaded, your emoji appears in the emoji picker for all workspace members to use.
  • You can upload animated GIFs as emoji, and they will play when used in messages.

How to upload an emoji on desktop

Open Slack in your web browser or desktop app and click your workspace name in the top left corner. Select "Customize Slack" from the menu that appears. This opens your workspace settings in a browser tab.

Click "Emoji" in the left sidebar. You will see a button labeled "Add Custom Emoji" (or sometimes "Upload an Emoji"). Click it, then select the image file from your computer. Slack will show you a preview of how the emoji will look. Type a name for it — this is what you type to insert it, like :my_emoji_name: — then click "Save".

The emoji appears in the emoji picker when ready. You can find it by typing its name in the search box, or scroll through the "Custom" section at the bottom of the picker.

How to upload an emoji on mobile

On iPhone or Android, tap your workspace name at the top of the screen, then tap "Settings". Scroll down and tap "Emoji". Tap the plus icon to add a new emoji.

Select a photo from your phone's camera roll or take a new photo. Crop it if needed, then type the emoji name and tap "Save". The emoji will be ready to use across your workspace within seconds.

Naming your emoji so others can find it

The name you give your emoji is how people type it into messages. Use lowercase letters, numbers, and underscores only — no spaces or special characters. Good names are short and descriptive: :thumbs_up:, :coffee_break:, :team_win:.

If you create an emoji that duplicates a standard Slack emoji name, your custom version will override it in your workspace. This is useful if you want a custom version of a common emoji, but it can confuse people if they expect the standard one.

Image requirements and file size limits

Slack accepts PNG, JPG, GIF, and animated GIF files. The image should be at least 128 pixels square, though Slack will accept smaller images and enlarge them (which may look blurry). Most people use 256 × 256 or 512 × 512 pixel images for the clearest result.

File size has no hard limit, but Slack recommends keeping images under 1 MB. Animated GIFs work as emoji and will play the animation when someone uses them in a message or reaction.

Removing or editing an emoji you created

Go back to Workspace Settings > Emoji and find the emoji you want to change. Click the three-dot menu next to it and select "Edit" to change the name, or "Remove" to delete it. Only the person who created the emoji can edit or remove it — admins cannot change someone else's custom emoji.

If you remove an emoji, any reactions using that emoji will disappear from messages where it was used. Removing an emoji is permanent and cannot be undone.

When custom emoji are restricted or not working

If you do not see the "Add Custom Emoji" button, your workspace admin has turned off the permission for regular members. Only admins can create emoji in that case. Ask your admin to either turn on the permission or create the emoji for you.

If you uploaded an emoji but it does not appear in the picker, check that the file format is supported (PNG, JPG, GIF, or animated GIF) and that the name contains only lowercase letters, numbers, and underscores. Refresh your Slack window and try searching for it by name.

Frequently Asked Questions

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

No. Custom emoji are specific to each workspace. If you want the same emoji in multiple workspaces, you will need to upload it separately to each one. You can take a screenshot of the emoji or save the original image file and upload it again.

What happens if two people create emoji with the same name?

The second person cannot create it — Slack will tell them the name is already taken. They will need to choose a different name. This prevents confusion about which emoji someone is referring to.

Can I create emoji from a URL or image on the internet?

No. You must read the image to your computer or phone first, then upload it through Slack. You cannot paste a URL directly into the emoji uploader.

Do custom emoji show up the same way for everyone in the workspace?

Yes. Once you upload a custom emoji, all workspace members see the exact same image when they use it or react with it, regardless of what device they are using.

Can I make an emoji that only certain people can see?

No. All custom emoji in a workspace are visible and usable by everyone in that workspace. There is no way to restrict an emoji to a specific person or channel.