Using Slack with Schedulin
Schedulin posts to Slack through the Schedulin app, installed in your workspace. You connect once with Slack's OAuth flow, then choose which channel each post goes to. You can schedule text, image, and video posts to Slack alongside every other platform.
Connecting Slack
- On Schedulin's Channels page, click Connect Slack.
- You'll be sent to Slack's authorization screen. Pick the workspace in the top-right corner if you're signed in to more than one, review the permissions, and click Allow.
- Slack installs the Schedulin app in that workspace and returns you to Schedulin, where the workspace appears in your channel list.
Some workspaces require an admin to approve new apps. If you see "Request to install" instead of Allow, ask a workspace admin to approve Schedulin, then connect again.
Schedulin publishes as its app, not as your personal Slack account, so posts show up from Schedulin in the channel.
To connect another workspace, click Connect Slack again and pick a different workspace. Each workspace is its own account in Schedulin.
Finding a channel ID
Slack connections are per-workspace, and you pick the target channel on each post:
- In Slack, open the channel you want to post to.
- Click the channel name at the top of the conversation.
- Scroll to the bottom of the About tab and copy the Channel ID (for example
C0123456789). - Paste that ID into the Channel ID field in Schedulin's composer.
Use the ID, not the channel name. IDs don't change when a channel is renamed.
Public and private channels
- Public channels: Schedulin joins the channel automatically the first time it posts there. Nothing to set up.
- Private channels: the app can't join on its own. Open the channel, click the channel name, go to Integrations → Add apps, and add Schedulin (or type
/invitein the channel and pick the Schedulin app). Then schedule the post.
What you can publish
| Post type | Media | How it appears in Slack |
|---|---|---|
| Text post | — | A message with your caption |
| Images | 1 or more images | Your caption with the images shown inline below it |
| Video | 1 or more videos (plus optional images) | The files uploaded to Slack and shared in one message, with your caption as the comment |
- Formatting: captions use Slack's formatting —
*bold*,_italic_,~strikethrough~, bulleted lists, and links. - Caption length: keep captions under 3,000 characters. Slack limits a single formatted text block to that length.
Required fields
Every Slack post needs a Channel ID — the channel the message is posted to (see Finding a channel ID above). Everything else (caption, media) is optional as long as the post isn't empty.
Analytics
Slack doesn't offer a metrics API for channel messages, so Schedulin does not report reactions, views, or engagement for Slack posts. Published posts still show as completed with a link to the message.
Troubleshooting
"Reconnect your Slack workspace to allow Schedulin to upload videos" — the workspace was connected before video support was added, so the connection doesn't have permission to upload files. Reconnect Slack from the Channels page and retry the post. Text and image posts keep working in the meantime.
"Add the Schedulin app to this Slack channel" — the channel is private (or the ID is wrong), so Schedulin can't post there. Invite the Schedulin app to the channel as described in Public and private channels, double-check the Channel ID, and retry.
"Choose a Slack channel for this post" — the Channel ID field was left empty. Add the channel ID in the composer and schedule again.
The workspace disappeared or posts fail after an admin change — if a workspace admin removed the Schedulin app, reconnect Slack from the Channels page to reinstall it.