Slack Emoji Size, Limits and How to Add Custom Emoji

A Slack custom emoji should be a square image, 128 × 128 px, under 128 KB, in PNG, JPG or GIF format. Slack's own help page asks for a square image under 128 KB with a transparent background, and animated GIFs can have up to 50 frames. Larger files are usually scaled down automatically.

This guide covers the emoji size and rules, how to add one, and the other Slack picture sizes people look for: the profile photo and the workspace icon.

Slack emoji size and limits

Slack's help page does not state a hard pixel size or a hard file size cut-off, and it does not publish a limit on how many emoji a workspace can have. The 128 × 128 px figure comes from how Slack displays emoji, and many guides report that bigger files are shrunk for you. Stick to the table and you will not run into problems.

To get a picture into the right shape and weight, the Slack photo resizer crops it to a square and exports it at the emoji, profile photo and workspace icon sizes in your browser.

How to add a custom emoji to Slack

On desktop:

1. Click the smiley face icon in the message box.
2. Click Add Emoji.
3. Click Upload Image and choose your file.
4. Type a name. This becomes the shortcode, such as :thumbsup_team:.
5. Click Save.

On iOS, tap the smiley face, enter a name, tap Add custom emoji, choose an image and tap Add. Adding emoji from the Android app is not currently supported, so use the desktop app or a browser.

Workspace owners can restrict who may add emoji. If you do not see the option, ask an owner or admin to add it or change the permission.

Make a custom emoji that looks good

Small details decide whether an emoji is readable at the size Slack shows it, which is about the height of a line of text.

• Keep one shape. A bold symbol or face beats a detailed picture. Crop tightly.
• Use a transparent background. It looks right in both light and dark mode. If you use a solid background, test it in dark mode.
• Add an outline. A thin light or dark edge helps the emoji stay visible on any theme.
• Name it clearly. Use words people will search for, such as ship_it or big_nope.
• Reduce file size. Export as PNG or a short GIF. If a GIF is heavy, cut frames or lower the colour count.

Slack emoji names and aliases

An emoji name has to be unique. If someone already used it, pick another. In practice use lowercase letters, numbers, dashes and underscores. An alias gives an existing emoji a second name, so :shipit: and :ship_it: can show the same picture. That helps when your team uses different spellings.

Slack profile picture size

For a Slack profile photo, upload a square image between 512 × 512 px and 1024 × 1024 px. Slack's help page says photos must be at least 512 × 512 px and no larger than 1024 × 1024 px.

What are the dimensions for a Slack profile picture?

Use a 512 × 512 px square or a little larger. Slack shows it as a small rounded square or circle depending on the view, so keep your face or logo in the middle.

To upload on desktop, click your profile picture in the sidebar, choose Profile, click Edit, then under Profile photo click Upload Photo, adjust the framing and save. On mobile, tap your picture, then View profile, Edit Profile and Edit Photo. If your Slack email matches a Gravatar, that image shows until you upload your own.

Slack workspace icon size

The workspace icon is the square logo in the top left of the Slack sidebar. A square 512 × 512 px PNG is a safe size. Slack shows it as a rounded square, so the corners of your image mostly remain visible.

How do I change my Slack workspace logo?

Workspace owners and admins can change it from the workspace settings, where the icon has its own upload button. Other members cannot change it. If you do not have a logo, the Slack workspace icon maker builds a 512 × 512 px icon from letters or an emoji.

What does the palm tree on Slack indicate?

The palm tree emoji in a Slack status usually means vacation or time off. Slack's own guidance for going on vacation suggests setting a status emoji to give more detail about your plans, and its example uses a beach island emoji; a palm tree is read the same way. You can also schedule the status in advance.

What size should emojis be for Discord?

Discord custom emoji are 128 × 128 px as well, so the same file works for both. The other Discord sizes are listed in Discord image sizes.

Frequently Asked Questions

What is the maximum size of a Slack emoji?

Slack says square images under 128 KB with transparent backgrounds work best. It does not state a hard cut-off, and larger files are often shrunk automatically, but keeping under 128 KB avoids trouble.

Can I use a GIF as a Slack emoji?

Yes. Slack accepts GIFs, up to 50 frames. Keep them small and short so they stay under about 128 KB.

Is there a limit on custom emoji per workspace?

Slack's help page does not state a limit. Third-party sources disagree, so if you plan to upload hundreds, test a batch first.

Why can't I add a custom emoji on Slack?

Either an owner has limited emoji uploads to admins, you are on the Android app, or the name is already taken. Try the desktop app, choose another name, or ask an admin.

Can I add emoji to my Slack profile?

You can set a status emoji from the status menu, and it appears next to your name. A custom emoji can be used there once it has been added to the workspace.

How do I make an emoji transparent for Slack?

Export a PNG with a transparent background from your editor. JPG cannot hold transparency, so use PNG or GIF.