TikTok vs YouTube Shorts vs Instagram Reels: video requirements compared

A vertical video can look identical on your phone and still be treated differently by each publishing API. The safest workflow is to keep one clean original file, then validate it against every destination before posting.

Quick reference

Limits documented by each platform for videos published through apps, checked on 12 October 2026:

• TikTok: MP4, WebM or MOV; H.264 preferred; 23 to 60 fps; 360 to 4096 pixels per side; up to 4 GB; up to 3 minutes for every creator (5 or 10 minutes for some accounts); caption up to 2,200 characters.
• YouTube Shorts: square or vertical; up to 3 minutes; title required, 100 characters maximum.
• Instagram Reels: MOV or MP4; H.264 or HEVC; 23 to 60 fps; up to 1920 pixels wide; 3 seconds to 15 minutes; up to 300 MB; professional account required.
• Facebook Reels: MP4, 9:16; 1080 × 1920 recommended, 540 × 960 minimum; 24 to 60 fps; 3 to 90 seconds; published to a Page.

A file that fits all four: MP4, H.264, AAC 48 kHz, 1080 × 1920, fixed 30 fps, 3 to 90 seconds, under 300 MB.

TikTok

TikTok's official Content Posting API accepts direct video posts from authorized apps. The app needs the video.publish permission, and the user must explicitly authorize it. TikTok also requires apps to query the creator's current privacy and interaction options before posting. Unaudited API clients are restricted to private posting until TikTok approves the integration.

TikTok — Media Transfer Guide

YouTube

YouTube uploads use the Data API's videos.insert method. Google documents a maximum upload size of 256 GB for this endpoint. Only square or vertical videos of up to 3 minutes are classified as Shorts. Uploads from unverified API projects created after 28 July 2020 are restricted to private viewing until the project passes an audit.

YouTube Help — three-minute Shorts · YouTube Data API — videos.insert

Instagram and Facebook Reels

Instagram publishing through Meta's official API is tied to eligible professional accounts and its publishing permissions. Facebook Reels published through the API go to a Page and run from 3 to 90 seconds. A technically valid video can still fail if the destination account is not eligible or the app lacks the required permission.

Meta — Instagram Reels specifications · Meta — Facebook Reels publishing

What to check before publishing

• File format and codec.
• Duration and file size.
• Resolution and aspect ratio.
• The exact account or Page being targeted.
• Visibility, disclosure and interaction settings supported by that destination.
• Whether the publishing app has passed the platform's required review.

Inktaro checks the video against each selected destination before publishing. It does not silently crop or trim the file to force it through.