> ## Documentation Index > Fetch the complete documentation index at: https://www.tella.com/docs/llms.txt > Use this file to discover all available pages before exploring further. # Video requirements for each social platform > The length, shape, size and audience limits Tella checks before publishing to YouTube, YouTube Shorts, LinkedIn, X, TikTok, Instagram and Facebook, and what each platform does with your title and description. Each platform sets its own limits on video length, shape and file size. Tella checks them before it exports your video. A platform your video breaks a limit for is greyed out under **Destinations** in the **Publish** tab, and hovering it says why: **Unavailable: landscape video**, **Unavailable: longer than 3 mins**, **Unavailable: shorter than 3 secs** or **Unavailable: 4K export**. If you change the video so it fits, the platform can be picked again. Lengths are measured on the video Tella uploads, so a video exported at 2× speed counts as half as long. ## Length, shape and size limits | Platform | Length | Shape | Other limits | | - | - | - | - | | **YouTube** | Up to 15 minutes until your channel is verified; longer after | Any | | | **YouTube Shorts** | Up to 3 minutes | Vertical or square | | | **LinkedIn** | 3 seconds to 30 minutes | Any | Up to 500 MB | | **X** | Up to 20 minutes; longer with X Premium or a verified checkmark | Any | | | **TikTok** | Set by TikTok for your account: 3 minutes for most, up to 10 for some | Any | | | **Instagram** and **Instagram Reels** | 3 seconds to 15 minutes | Any | Up to 300 MB; no 4K | | **Instagram Stories** | 3 seconds to 60 seconds | Any | Up to 100 MB; no 4K | | **Facebook** | No limit checked by Tella | Any | | | **Facebook Stories** | 3 seconds to 60 seconds | Vertical | | YouTube, X and TikTok set their limits per account, so Tella reads yours once the account is connected. For example, a 20-minute video on a YouTube channel that isn't verified shows **Unavailable: longer than 15 mins**. File size is only known once the video is exported, so Tella checks it just before uploading. If a video is too big, publish a shorter version or lower the size under **Export settings**. ## Why can't I publish 4K to Instagram? Instagram takes video at most 1920 pixels wide, so with a 4K size the Instagram platforms show **Unavailable: 4K export**. Set the size to HD under **Export settings** before publishing to **Instagram**, **Instagram Reels** or **Instagram Stories**. Tella doesn't block 4K for the other platforms, on plans that export 4K. ## Why won't YouTube Shorts or Facebook Stories take my video? Both need an upright video: YouTube Shorts takes vertical or square, and Facebook Stories takes vertical. A landscape video can't be posted there. Change the video's format in the editor first, then publish. YouTube has no separate upload for Shorts: any vertical or square video of 3 minutes or less becomes a Short. ## Who can see the post on each platform? Choose the audience under **Who can see it** on the platform's tab in **Post details**. | Platform | Audiences | | - | - | | **YouTube**, **YouTube Shorts** | **Public**, **Unlisted**, **Private** | | **LinkedIn** | **Anyone**, **Connections only** | | **Facebook** | **Everyone**, **Anyone with the link**, **Only people who manage the Page** | | **TikTok** | The audiences TikTok offers your account, such as **Everyone**, **Followers**, **Friends** or **Only you** | | **X**, **Instagram**, **Facebook Stories** | Everyone | ## What each platform does with the title and description | Platform | Title | Description | | - | - | - | | **YouTube**, **YouTube Shorts** | The video title | The video description, with chapters added if you choose | | **LinkedIn**, **X**, **TikTok**, **Instagram**, **Facebook** | Used as the post text when the description is empty | The post text | | **Instagram Stories**, **Facebook Stories** | Not shown | Not shown | X allows 280 characters, or 25,000 with X Premium or a verified checkmark, and TikTok up to 2,200. The character count shows under the description on those platforms' tabs. ## Subtitles on each platform Only YouTube and YouTube Shorts take caption tracks, which Tella uploads from your transcript and any translated subtitles. Everywhere else, turn on **Burn subtitles into the video** under **Export settings** to show subtitles. ## Related topics - [Publish a video to social media](/docs/help/sharing/publish-to-social-media.md) - [Why did my video fail to publish?](/docs/help/sharing/social-publishing-failed.md) - [Publish to social media with the API or MCP](/docs/help/integrations/publish-with-the-api-and-mcp.md) - [Agent skills guide](/docs/help/integrations/agent-skills.md) - [Preview social safe zones](/docs/help/editing/social-safe-zones.md)