Setup guides
Everything Postline needs, step by step with screenshots. Do them in this order the first time.
Video storage (Backblaze B2)
Postline keeps your queued videos in your own storage bucket until they post, then deletes them. Backblaze B2 gives 10 GB free without a card - enough for a few hundred short videos waiting at once.
About 5 minutes · free, no card
YouTube
Postline uploads Shorts to your YouTube channel through Postline's own Google app - you don't set up anything in Google Cloud. You sign in with Google once per channel; Postline can only upload videos and read the channel's basic stats.
About 1 minute per channel
Facebook Page & Instagram
Postline posts Reels to a Facebook Page and its linked Instagram account. Instagram must be a Professional account linked to the Page. You make your own Facebook app once and add it to Postline; after that every Page connects with one click.
About 15 minutes the first time, then 1 minute per Page
TikTok
Sign in with TikTok once per channel. Each video then goes to that TikTok account at the channel's posting times - either as a draft in the TikTok app's inbox, or straight to the profile.
About 1 minute
How to upload videos
Uploads go one channel at a time. Put a channel's videos in one folder, add a text file next to each video for its title and caption, and pick the folder - Postline queues them all in order and posts them on the channel's schedule.
A few minutes per batch
Post with an AI agent or your own code (API)
Give your AI agent (Claude, ChatGPT, Cursor, Claude Code…) one prompt and a key. It asks which channel and which videos, then uploads and posts them - queued for the next time slot, or right away. Developers can call the same API directly.
About 2 minutes with an agent