Platform Capabilities

Supported post types, capability matrix, and recommended media formats for every connected platform.

Supported Platforms

Octapost supports publishing to seven social platforms. Each platform has its own set of supported post types, media requirements, and API constraints. Use this page as a reference when preparing content so your media always meets each platform's specifications.

FacebookInstagramX / TwitterLinkedInTikTokRedditYouTube

Capability Matrix

The table below shows which post types Octapost supports for each platform. A dash means the platform does not support that post type via its API, or Octapost does not yet implement it.

Platform	Text	Image	Carousel	Video (feed)	Reels / Shorts	Stories
Facebook	âœ“	âœ“	âœ“	âœ“	âœ“	â€”
Instagram	âœ“	âœ“	âœ“	âœ“	âœ“	âœ“
X / Twitter	âœ“	âœ“	â€”	âœ“	â€”	â€”
LinkedIn	âœ“	âœ“	âœ“	âœ“	â€”	â€”
TikTok	âœ“	âœ“	âœ“	âœ“	âœ“	â€”
Reddit	âœ“	âœ“	â€”	âœ“	â€”	â€”
YouTube	â€”	â€”	â€”	âœ“	âœ“	â€”

Reels / Shorts on Facebook and Instagram use the same 9:16 vertical video format. TikTok videos are inherently short-form. YouTube Shorts are regular video uploads with a duration of 60 seconds or less — Octapost appends #Shorts to the description automatically.

Feed — Image

Recommended image specifications for standard feed posts. Always use the highest resolution possible — platforms re-compress images during upload.

Platform	Recommended Size	Accepted Aspect Ratios	Max File Size	Formats
Facebook	1200 × 630 px	1.91:1 (landscape) to 4:5 (portrait)	30 MB	JPG, PNG, GIF
Instagram	1080 × 1080 px (1:1) or 1080 × 1350 px (4:5)	4:5 (portrait) recommended for feed	8 MB	JPG, PNG
X / Twitter	1200 × 675 px	2:1 to 1:1	5 MB (JPEG/PNG), 15 MB (GIF)	JPG, PNG, GIF, WEBP
LinkedIn	1200 × 627 px	1.91:1	5 MB	JPG, PNG, GIF
TikTok	1080 × 1920 px (9:16)	9:16 required for photo posts	20 MB per image	JPG, PNG, WEBP
Reddit	1200 × 628 px	Any — 1:1 displays cleanly	20 MB	JPG, PNG, GIF

For multi-platform posts, a 1080 × 1080 px (1:1) JPG is the safest choice — it displays well on every platform and keeps file size small.

Feed — Video

Specifications for standard (non-vertical) video posts in the feed. For vertical short-form video see the Reels & Shorts section below.

Platform	Aspect Ratio	Max Duration	Max File Size	Codec
Facebook	16:9 landscape (1:1 also accepted)	4 hours	10 GB	H.264 / MP4
Instagram	4:5 (portrait) or 1:1 for feed	60 min	500 MB	H.264 / MP4
X / Twitter	16:9 or 1:1	2 min 20 sec	512 MB	H.264 / MP4
LinkedIn	1:2.4 to 2.4:1	10 min	5 GB	H.264 / MP4
TikTok	9:16 (vertical)	10 min	2 GB	H.264 or H.265 / MP4
Reddit	16:9	15 min (900 sec)	1 GB	H.264 / MP4
YouTube	16:9 (landscape)	No hard limit	256 GB or 12 hours	H.264 / MP4 or MOV

Reels & Shorts

Short-form vertical video is the highest-reach post type across all platforms that support it. All reels and shorts require a 9:16 aspect ratio (1080 × 1920 px).

Platform	Name	Max Duration	Max File Size	Notes
Facebook	Facebook Reel	90 sec	4 GB	Music and audio overlay via Facebook Creator Studio after publishing
Instagram	Instagram Reel	90 sec (3 min for eligible accounts)	1 GB	Cover image extracted automatically from the first frame
TikTok	TikTok Video	10 min	2 GB	TikTok's native format — all TikTok videos are short-form by default
YouTube	YouTube Short	60 sec	256 GB (same as regular video)	Octapost automatically adds #Shorts to the description

Record at 1080 × 1920 px (or higher and crop in the asset editor) and export as H.264 MP4 for maximum compatibility across all four reel/short-form platforms.

Stories

Stories are ephemeral content that disappears after 24 hours. Currently only Instagram Stories are supported by the Octapost publisher.

Platform	Aspect Ratio	Image Max Size	Video Max Duration	Ephemeral
Instagram	9:16 (1080 × 1920 px)	30 MB	60 sec per story card	Yes — disappears after 24 hours

Instagram Stories cannot be scheduled — they are published immediately when you click Publish Now. The schedule option is hidden when the story post type is selected.

Use full-bleed 9:16 images or vertical video for best display.
Avoid placing important content in the top 250 px (UI overlays) or bottom 250 px (swipe-up area).
Instagram saves a copy to your Highlights if you pin it — this does not happen automatically via the API.

Text & Caption Limits

Octapost shows a live character counter in the composer and warns you when you approach a platform's limit. The limits below are the hard API maximums.

Platform	Caption / Post Limit	Notes
Facebook	63,206 characters	No practical limit for most use cases
Instagram	2,200 characters	Only the first ~125 chars show before "more"
X / Twitter	280 characters	Long posts are split into threads automatically
LinkedIn	3,000 characters (personal) / 700 (company page)	Company page posts truncate sooner in the feed
TikTok	2,200 characters	First ~100 chars visible before "more"
Reddit	40,000 characters (text post) / 300 (title)	Link posts have no body — title is the only text
YouTube	5,000 characters (description)	Title is capped at 100 characters