> ## Documentation Index > Fetch the complete documentation index at: https://docs.publishbuddy.com/llms.txt > Use this file to discover all available pages before exploring further. # How long can my post be, and how big can my files be? > The character, image and video limits PublishBuddy checks for each network, and where the network's own rules take over. PublishBuddy checks some limits when you save a post. This page lists every limit it checks. Where a cell says **Not checked**, PublishBuddy doesn't test it, and the network's own rules apply. If the network refuses a file, the post fails when it's published. See [My post failed](/help/troubleshooting/post-failed). ## Limits for every post | What | Limit | | - | - | | Media files per post | 8 | | Size of each file you upload | 2 GB | | File types | Images and videos | | Text box | 5,000 characters | | Files in a **Reel** or **Story** | 1 | | Follow-up comment text | 1,000 characters | | Media in a follow-up comment | 1 file | Some networks allow fewer files. They're listed below. ## Image and video limits for each network | Network | Images | Video size | Video length | Files per post | | - | - | - | - | - | | Facebook Page | Not checked | Not checked | Not checked | 8 | | Instagram | Up to 8 MB | Up to 1 GB | 3 seconds to 15 minutes | 8 | | LinkedIn | Not checked | Up to 5 GB | Up to 10 minutes | 8 | | X | Up to 5 MB | Up to 512 MB | Up to 140 seconds | 4 | | Threads | Up to 8 MB | Up to 1 GB | Up to 5 minutes | 8 | | Bluesky | Up to 2 MB | Up to 50 MB | Up to 60 seconds | 4 | | Telegram | Not checked | Not checked | Not checked | 8 | | TikTok | Up to 20 MB | Up to 1 GB | 3 seconds to 10 minutes | 8 | | Pinterest | Not checked | Not checked | Not checked | 5 | | YouTube | No images | Not checked | Not checked | 1 video | A few extra rules: * **X** videos must be MP4 or MOV files. * **Instagram** carousels that mix photos and videos can't include a 9:16 video. * **Telegram** posts that mix photos and videos need MP4 videos with sound. * **TikTok** also checks your account's own video length limit when it publishes. Some accounts can only post shorter videos. * **LinkedIn** allows bigger videos than you can upload. The 2 GB upload limit still applies. The Instagram limits apply whether the account uses the Facebook login or the Instagram login. ## What you'll see when a file is over the limit When you save, PublishBuddy names the check that failed: | Message | What to fix | | - | - | | "Image size validation failed." | An image is too big for one of the networks. | | "Video size validation failed." | A video is too big. | | "Video duration validation failed." | A video is too long or too short. | | "Video type validation failed." | The video format isn't allowed (X only takes MP4 or MOV). | | "Media contents count validation failed." | Too many files for one of the networks. | | "Mixed media contents validation failed." | That network can't take this mix of photos and videos. | If the message includes "by comment", the problem is in a follow-up comment, not the post itself. When several accounts are in one post, the strictest limit wins. For example, an image of 4 MB works on Instagram but stops a post that also goes to Bluesky. Make a separate post for Bluesky with a smaller image. ## Character limits Right now, PublishBuddy only checks caption length for Bluesky. A Bluesky caption over 300 characters stops with "Bluesky caption must be 300 characters or less." On every other network, the network's own caption limit applies. If your text is too long, the network refuses the post and it fails. The composer has no character counter, so check long captions before you schedule them. Pinterest cuts text when the Pin goes out. The title is cut to 100 characters and the description to 500, with no warning. See [Pinterest options](/help/posts/pinterest-options). ### Follow-up comments Comments get checked against the network's limit too. A comment is capped at 1,000 characters, or less on these networks: | Network | Comment limit | | - | - | | X | 280 characters | | Bluesky | 300 characters | | Threads | 500 characters | A comment over the limit stops with "Comment text validation failed." The comment limits count an emoji as 4 characters and an accented letter as 2. The Pinterest cut works the same way. Leave some room if you use them. ## Thumbnails You can add a custom thumbnail to a video for these networks: | Network | File type | Size | | - | - | - | | YouTube | JPG or PNG | Up to 2 MB | | Instagram (through Facebook) | JPG | Up to 8 MB | | Facebook Page | JPG or PNG | Up to 10 MB | When the video goes to more than one of these, the strictest rule applies. The tile shows a message like "Thumbnail must be a JPG image for the selected network(s)." if your image doesn't fit. ## Related * [Post types and limits for each network](/help/limits/post-types-by-network) * [Change a post for just one network](/help/posts/customize-per-network) * [My post failed](/help/troubleshooting/post-failed) This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.