How to Make a Slack Emoji From a Picture (Free, 2 Minutes)

To make a Slack emoji from a picture, crop the photo to a square around one subject, scale it to 128 by 128 pixels, remove the background if it is a plain color, and save it as a PNG under 128 KB. Then in Slack click the smiley face in the message field, Add Emoji, Upload Image, give it a name, and save. Our free Slack emoji maker does the crop, scaling and background removal in your browser, and can animate the result. A 417 KB photo we ran through these steps came out at 32 KB.

We build Slack Green, which keeps your Slack status green during your work hours, and a set of free Slack tools, including the emoji maker.

Make a Slack emoji from a picture in the browser

• Open the Slack emoji maker and keep Image to emoji selected.
• Drop the picture in, click to choose it, or paste it. PNG, JPG, GIF and WebP work, and a screenshot on your clipboard pastes straight in.
• Leave Crop to a square on and use Zoom, Left/right and Up/down to frame one face, logo or object. Fit whole image keeps everything but adds empty space.
• Tick Remove background if the subject sits on a plain color. It clears the color around the edges.
• Check the previews at 16, 22 and 32 pixels on light and dark themes. If the subject is hard to see at 22 pixels, zoom in more.
• Optional: pick an effect such as intensifies, party or spin to make it an animated GIF.
• Click Download PNG (or GIF). The tool suggests an emoji name from the file.

The picture never leaves your computer. Every output is 128 by 128 pixels and under Slack's 128 KB guideline.

Crop, size and file rules for a picture emoji



Slack's help center asks for a square JPG, PNG or GIF, under 128 KB, ideally with a transparent background. An emoji shows at about 22 pixels in a message and 32 pixels when it is posted alone, so the picture has to read at that size.

We took a 512 by 512 pixel photo of a parrot, 417 KB as a PNG, which Slack would not take as an emoji. Cropping tight around the head and scaling to 128 by 128 brought it to 32 KB. At 22 pixels the red head and yellow beak still read; the eye does not. That is the usual trade: color and shape survive, detail does not.

If you prefer the command line, ImageMagick does the crop and scale in one line:

# Fill a 128x128 square from the center, drop metadata
magick photo.jpg -resize 128x128^ -gravity center -extent 128x128 -strip emoji.png

# Check the size is under 128 KB
ls -l emoji.png

On a Mac without ImageMagick, the built-in sips works too:

sips -c 440 440 photo.png --out crop.png   # center crop to a square
sips -z 128 128 crop.png --out emoji.png   # scale to 128 x 128

Our parrot came out at 30.5 KB with ImageMagick and 35.3 KB with sips.

Tips by picture type



Picture	How to crop	Background	Tip
Face or selfie	Head only, chin to hair	Remove it if it is plain	A big expression reads better than a neutral one
Logo	The symbol, not the full wordmark	Use a transparent PNG	Thin lines vanish at 22 px, so thicken them
Pet photo	Face, ears to chin	Often busy; keep it	High contrast against the fur helps
Screenshot	One icon, word or number	Keep it, or crop it out	Only large text survives
Product photo	The object alone	Remove it if the shot is on white	Use a photo taken on a plain background

A picture with a white background shows a white square on dark mode. Remove it in the emoji maker, or see how to make an emoji background transparent for Slack. A picture of a coworker needs their OK first; everyone in the workspace can use a custom emoji once it is added.

Add the picture emoji to Slack

You can add emoji from the desktop app, the browser, and the iPhone or iPad app, but not from Android. Some workspaces let only admins add emoji. The full steps and the permission rules are in how to add custom emoji to Slack.

If Slack says the file is too big, the Slack emoji resizer shrinks it under 128 KB. If the picture looks tiny in messages, see how to make Slack emoji bigger.

Other ways to make an emoji from an image

FAQ

Can I turn any picture into a Slack emoji? Yes, if it is a JPG, PNG or GIF. Crop it to a square and keep it under 128 KB so Slack accepts it.

What size should a Slack emoji be? 128 by 128 pixels, square, under 128 KB. Bigger images do not show bigger.

How do I make an emoji of my face for Slack? Take a photo against a plain wall, crop to your head in the emoji maker, tick Remove background, and upload the PNG.

Is the Slack emoji maker free? Yes. No account, no watermark, and your picture stays on your computer.