What social platforms officially accept: upload specs and 10 contradictions (2026)
Codecs, containers, image sizes and safe zones that 16 platform surfaces document, compiled only from official help centres and API references, with 10 places where official sources contradict each other or popular guides.
How we compiled it
Only official sources count: platform help centres, API references and ad specs. Each value links to the platform page that holds its source and check date, and the text of every source we read is archived. Where a platform says nothing, the table says "Not documented", never "rejected". Statuses mean: Recommended (the platform names it as the preferred upload), Accepted, Accepted and re-encoded, Conditional, Not documented, and Non-standard (a combination that rarely exists).
10 contradictions in official specs
Meta's safe-zone help article no longer gives numbers
Meta's general article on safe zones for Reels now only says to keep the edges clear (and the bottom 40% for disclaimers). The figures guides quote, 14% top, 35% bottom and 6% each side, now appear only in the Ads Guide's Reels video specs.
Source: Meta Business Help: safe zones for Reels · Meta Ads Guide: Instagram Reels video · Instagram Reels safe zone
Instagram documents HEVC, but only in its API reference
The Instagram API spec for reels, stories and videos lists "HEVC or H264" in MOV or MP4. Instagram's help centre publishes no codec list for app uploads, so the common advice that Instagram needs H.264 is incomplete rather than wrong.
Source: Instagram API: IG User Media · What is HEVC?
Two official Instagram ranges for photo shape
Instagram's help centre keeps photos uncropped from 1.91:1 to 3:4 (up to 1080 × 1440). Its API image spec gives 4:5 to 1.91:1. A 3:4 portrait is fine in the app but outside the API range.
Source: Instagram Help: Image resolution of photos you share · Instagram API: IG User Media · Instagram portrait post size
YouTube's format list does not name AV1 or MKV
YouTube recommends H.264 in MP4. Its supported-formats list includes MOV, MP4, WebM and HEVC, but neither AV1 by name nor MKV. VP9 is accepted through WebM, not recommended.
Source: YouTube Help: Recommended upload encoding settings · YouTube Help: Supported YouTube file formats · YouTube codec matrix
YouTube now recommends 4K thumbnails
YouTube recommends 3840 × 2160 thumbnails for videos (2160 × 3840 for Shorts), with a minimum width of 640 px. Most guides still give 1280 × 720, which remains accepted.
Source: YouTube Help: Add custom thumbnails · YouTube thumbnail size
The 820 × 312 Facebook cover size is not in Facebook's help
Facebook's help article gives a 400 × 150 minimum and says covers load fastest as an sRGB JPG of 851 × 315 under 100 KB, cropped to 16:9 on computers and 2.4:1 on phones. The widely repeated 820 × 312 does not appear.
Source: Facebook Help: Page profile picture and cover photo dimensions · Facebook cover photo size
Facebook publishes no organic post image size
The only official Feed image numbers, 1440 × 1800 (4:5), JPG or PNG, up to 30 MB, come from the Meta Ads Guide. Organic posts appear in the same Feed but have no separate spec.
Source: Meta Ads Guide: Facebook Feed image · Facebook post image size
YouTube gives no upload size for profile pictures
YouTube states the picture renders at 98 × 98 px and must be JPG, GIF, BMP or PNG up to 15 MB. The 800 × 800 size most guides give is a convention, not a YouTube figure.
Source: YouTube Help: Manage your channel branding · YouTube profile picture size
Four platforms publish no safe-zone figures
Snapchat, X, Threads and LinkedIn publish no official safe-zone percentages for their vertical video surfaces. Figures circulating for them are third-party estimates.
No official source exists, which is the finding. · Safe zones by platform
YouTube Shorts earnings get a 10-million-view threshold
From 1 February 2027, YouTube requires at least 10 million qualified Shorts views in the last 90 days to earn a share of Shorts ad revenue. Creators keep 45% of revenue allocated from the Shorts Creator Pool.
Source: YouTube Help: YouTube Shorts monetization policies · YouTube earnings calculator
Video codecs by platform
Containers by platform
Image sizes the platforms state
* The platform states only a ratio, display size or limits; the size shown is our recommendation within them.
Safe zones on vertical video
| Platform | Figures | Keep clear |
|---|---|---|
| TikTok | Official | Top 12.5%, bottom 34.4%, left 11.1%, right 11.1% |
| Instagram Reels | Official | Top 14%, bottom 35%, left 6%, right 6% |
| Facebook Reels | Official | Top 14%, bottom 35%, left 6%, right 6% |
| YouTube Shorts | Official | Top 15%, bottom 35%, left 4.4%, right 17.8% |
| Snapchat | Not published | No official figures; see the platform page for what is known |
| Official | Top 14.1%, bottom 41.1%, left 6%, right 18.1% | |
| Not published | No official figures; see the platform page for what is known | |
| Threads | Not published | No official figures; see the platform page for what is known |
| X (Twitter) | Not published | No official figures; see the platform page for what is known |
| Instagram Feed | Approximate | No official figures; see the platform page for what is known |
Using this data
Quote any figure with a link to this page. Tables update when a platform changes its documentation; the check date above shows the last full review, and each platform page shows its own.