sizefit

Home/Slack

Shrink a screen recording before posting it in Slack

Screen recordings are the classic Slack file: long, sharp, and bigger than they need to be. Squeeze one down so it loads right in the thread.

  • Nothing is uploaded. Your browser does the compression, so the file stays on your device.
  • Lands under the real limit. We aim a little below it, so the upload goes through first time.
  • Fast. A 30 second 1080p clip fits into 10 MB in about two seconds on a desktop.
Where are you sending it?

Typical limit 25.00 MB. We aim for 24.00 MB, 1.00 MB of safety margin. Typical size, not an official limit (see source for the official figure), checked November 2026. Source Slack's official limit is 1 GB per file. 25 MB is our light size, not a limit.

Sent to our servers: 0 bytes. It all happens in this tab.

How the Slack limit works

Slack accepts large files, but your workspace admin can set a lower limit, and big videos are slow to open in a thread. A clip under 25 MB loads almost instantly for everyone.

A screen recording is mostly static, which makes it ideal for compression. Text stays readable at a surprisingly small size because little changes between frames.

Sizes we target

  • Slack, shareable 100 MB: Slack lets workspaces upload large files, but 100 MB keeps channels quick to open. Your admin may set a lower cap. (typical size, not an official limit) Source (checked 2026-11-09)
  • Slack, light 25 MB: A comfortable size for sharing clips in busy channels. (typical size, not an official limit) Source (checked 2026-11-09)

We aim below each limit by the margin shown. Use the menu above to switch.

Tips

  • Record at your normal screen size and let us scale it. Zooming the recording yourself loses sharpness.
  • Add a one-line description when you post. Nobody wants to press play to find out what a clip is about.

Questions people ask

What is Slack's file size limit?

Slack allows large uploads, and workspaces may restrict them further. See the Slack help link above for the current figure.

Will text in my screen recording stay readable?

Usually yes. If it looks soft, pick a larger size such as 100 MB, or trim the clip.

Related

Limits change. We link the official page wherever there is one, and the safety margin means a small change is unlikely to matter. Last updated 2026-11-09.