Is my photo uploaded to resize it for Slack?

No. The photo is framed, resized and encoded in your browser, and nothing is sent anywhere.

Are these the official Slack sizes?

They are the pixel sizes Slack publishes or recommends for each place, as of 2026. Slack may change them and always recompresses uploads, so check its help pages for anything critical.

Why does my photo look soft?

When the photo has fewer pixels than the size you chose, it is enlarged and loses sharpness. The tool warns you when that happens; start from a bigger original if you can.

Slack Photo Resizer

Resize and crop a photo to Slack's sizes: profile photo, workspace icon, custom emoji and more.

Frame

Slack sizes

File type

Runs in your browser; nothing you enter leaves this page.

How it works

Slack sizes

The tool knows 4 places on Slack where you upload a picture, and frames your photo for each one:

Profile photo: 512 × 512 px

Workspace icon: 512 × 512 px

Custom emoji: 128 × 128 px

App icon: 512 × 512 px

Framing and saving

The photo is scaled up just enough to cover the frame, and the part you see is what is saved. Drag the picture, nudge it with the arrow keys, zoom in with the slider, or rotate it a quarter turn. In the case of profile photo, the output is 512 × 512 px.

Choose PNG for a lossless file or JPEG for a smaller one, then download one size, or every size for the platform in a single zip.

More tools

All 238 tools

Matte GeneratorFit a photo into a 1:1, 4:5, 3:4 or 9:16 frame without cropping, on a blurred copy, a solid colour or a gradient.
Scroll Carousel SplitterCut a wide image into equal 4:5, 1:1 or 3:4 slides for a swipeable carousel that reads as one picture.
Social Media CropperCrop a photo to the aspect ratios of Instagram, Facebook, Bluesky, LinkedIn, Mastodon, Pinterest, Threads, TikTok and YouTube.
WatermarkerStamp text or a logo on a photo: position, size, opacity, blend mode, or tile it across the whole picture.