Instagram can schedule a post by itself now, from a professional account in the app, up to 75 days ahead. So the first question is why anyone uses a tool. The answers are the usual ones: the same post goes to five other networks, a client has to approve it first, the caption needs checking against rules the app does not show you until it refuses, and the person scheduling is not the person whose phone the account is on. This page says what Instagram's API lets a tool do, where it refuses, and how Preflight handles each case.
The account and the connection
The Content Publishing API works for professional accounts only. Preflight asks for an Instagram Business account connected through Facebook Login; a personal account cannot be scheduled by any tool, and switching to a professional account is free and takes a minute in the app. The token Meta hands out lasts about 60 days and Preflight renews it in the background; if Instagram revokes it (a password change, a security review), the channel asks to be reconnected and keeps its history.
Pictures are not uploaded to Instagram. The API fetches them from a URL the tool provides, so the tool hosts the file for the minute it takes. Instagram accepts JPEG only; Preflight converts a PNG or WebP before Instagram sees it.
What the API publishes
| Format | What is allowed | Where Preflight checks |
|---|---|---|
| Feed picture | JPEG, up to 8 MB, 4:5 to 1.91:1 | Ratio refused in the composer; conversion at publish |
| Carousel | 2 to 10 pictures or videos, mixed | Count and each file's ratio |
| Reel | MP4 or MOV, 3 seconds to 15 minutes, 23 to 60 fps, up to 300 MB; cover image; share to feed on or off; collaborators | Duration, fps, size before upload |
| Trial reel | A reel shown to non-followers first, graduated by hand or on performance; no collaborators | Collaborators dropped rather than failing |
| Story | One picture or one video of 3 to 60 seconds up to 100 MB; no caption, no carousel | Duration and size |
| Caption | 2,200 characters, 30 hashtags, 20 @mentions | Counted while typing; over the limit is refused |
| First comment | Posted right after the post, where hashtags usually go | Same limits |
| Alt text | Per picture | Sent with each file |
A video in a normal post is published as a Reel; the API has no other kind of video post. The details behind each number are on the Instagram limits page, and the same figures for eleven other networks on the limits table.
What no tool can do
- Edit a published caption. The API deletes; it does not edit. Preflight can delete a post from the dashboard and that is all.
- Stickers, links, music or mentions on a story. A story from the API is the plain picture or video.
- Product tags, location tags, music on a Reel. The API supports some of these; Preflight does not send them yet.
- More than 100 posts in 24 hours per account. Instagram counts API-published posts; a carousel is one.
- Direct messages. Not in the publishing API at all.
Scheduling in Preflight
Write the post once and tick Instagram among the targets. The composer counts 2,200 characters for Instagram beside 500 bytes for Threads and 300 graphemes for Bluesky, counts the hashtags and mentions, and reads each picture's ratio and each video's length and frame rate before anything is uploaded. Choose feed, Reel or story per target; pick a cover frame for the Reel; add the first comment and alt text. A client who has to sign off gets an approval link, no account needed. The post goes to the queue or to a fixed minute, and after publishing Preflight reads back views, likes, comments, shares, saves and reach, and for Reels the watch time. Comments can be read, answered, hidden and deleted from the inbox.
The free plan takes three channels, so an Instagram account, its Facebook Page and one more; plans are on the pricing page.
Instagram against TikTok
The two short-video networks accept different files. Instagram wants 4:5 to 1.91:1 pictures and a Reel up to 15 minutes; TikTok wants 360 to 4,096 pixels on each side, 23 to 60 fps, up to 10 minutes but often less for a given creator, and sends a photo post's first line out as a 90-character title. A clip that passed one can fail the other; the TikTok side is on how to schedule TikTok posts.
Questions people ask
- Can you schedule Instagram posts natively?
- Yes, from a professional account in the app, up to 75 days ahead. A tool is for cross-posting, approvals, checking the caption against the rules first, and publishing from a desk rather than the account owner's phone.
- Do I need a Business account to schedule Instagram posts with a tool?
- Yes. Instagram's publishing API works for professional accounts only; Preflight asks for a Business account connected through Facebook Login. Switching from a personal account is free.
- Can a tool post Instagram stories?
- Yes, one picture or one video of 3 to 60 seconds, up to 100 MB. The API adds no stickers, links, music or mentions, so a story from any tool is the plain media.
- Why was my picture refused?
- Usually the ratio: feed pictures must sit between 4:5 and 1.91:1, and a square-cropped screenshot or a tall phone photo is outside that. Preflight says so in the composer; crop and try again.