X video length: limits, file sizes, and formats

The practical X video length limit is 20 minutes on a default account and 125 minutes with X Premium or a verified subscription, with file sizes capped at 8 GB and 16 GB respectively. Minimum length is half a second. Those are X's own published numbers, and X's documentation says plainly that the post-video caps match the X app (X Developer Platform, September 2026).

If you searched this and found "2 minutes 20 seconds," you found a figure that is years out of date for posts, and it is still sitting at the top of the results.

#The 140-second answer is wrong, and here is why it persists

Nearly every video-specs page currently ranking says a free account gets 140 seconds and 512 MB. That pairing is real, but it belongs to a different surface: it is the cap for video sent inside a Direct Message on a default account. It was also the post limit on Twitter years ago, which is how it got copied into a hundred guides and then copied out of them again.

X raised the free post limit and did it quietly. RouteNote noticed the desktop web bump in April 2025, when non-Premium uploads went from 140 seconds to roughly ten minutes. X's current media documentation puts the default post cap at 20 minutes.

There is a lesson here worth more than the number. Specs pages age badly because nobody rechecks them, so before you plan a long video around a figure from a blog, test a short upload from the client you actually post from.

#X video limits, by account and surface

Minimum duration is 0.5 seconds everywhere. One post carries up to 4 photos, or 1 animated GIF, or 1 video, never a mixture.

Two caveats that matter in practice. First, these caps follow the account doing the posting, not the tool doing the uploading, so a scheduler cannot buy you length your account does not have. Second, client rollouts have historically been uneven between web, iOS and Android, and long uploads have landed on one before the others. If a long video refuses on your phone, try x.com in a browser before you conclude the limit changed.

#Upload limits and posting limits are two different gates

This is the part that causes the confusing failures. X checks your file when you upload it, then checks it again when you attach it to a post. Passing the first gate does not mean passing the second.

When the second gate rejects a video for length, X returns a 403 with a message that names your actual cap: This user is not allowed to post a video longer than N minutes. That error is genuinely useful, because N is the real number for your account today. It beats any table on the internet, including the one above.

So if a 40-minute upload completes and then the post fails, nothing is broken. You uploaded fine and you are not entitled to post that length.

#Format and encoding: what actually breaks uploads

Length gets all the attention and causes a minority of failures. Encoding causes most of them. X's published requirements:

Recommended

• Container and codec: MP4 with H.264 High Profile
• Audio: AAC Low Complexity, 128 kbps or better, mono or stereo
• Resolution: 1280x720 landscape, 720x1280 portrait, or 720x720 square
• Frame rate: 30 or 60 fps
• Video bitrate: 5,000 kbps or higher
• Aspect ratio: 16:9 or 1:1

Hard requirements

• Frame rate of 60 fps or under
• Dimensions between 32x32 and 1280x1024
• Aspect ratio between 1:3 and 3:1
• Pixel aspect ratio of exactly 1:1
• YUV 4:2:0 pixel format, progressive scan, no open GOP

Read that second list again if uploads keep failing. High-Efficiency AAC audio is rejected where AAC-LC is accepted, 5.1 surround is rejected where stereo is accepted, and an interlaced export is rejected where a progressive one sails through. None of those produce an error message that tells you what went wrong.

MOV files are accepted and are also the most common source of "your media file could not be processed." Re-export as MP4 first and you will resolve more upload problems than any other single change.

#Resolution, and why 4K is wasted effort

X ties playback quality to subscription status. Subscribers can upload 1080p and get 1080p playback. Non-subscribers get 720p playback regardless of what they hand over.

That has a blunt consequence: if you do not subscribe, exporting at 4K costs you a long upload and a big file and delivers exactly the same 720p stream to viewers. Export at 720p, spend the bitrate instead, and your video will look better than a downscaled 4K file at the same perceived size.

For anything text-heavy on screen, the same rule from X image sizes applies: type that looks fine on your monitor turns to mush at roughly 500 px wide on a phone. Set on-screen text far larger than feels right.

#How to post a video on X

On the web (x.com)

1. Click the compose box or the post button.
2. Drag the file in, or click the media icon and pick it.
3. Wait for the preview. Trim if you want, using the scissors control.
4. Add your text, remembering the X character limit still applies to the caption.
5. Post.

In the app

1. Tap the compose button, then the gallery icon.
2. Select the clip and trim it in the editor.
3. Tap the accessibility or captions option to add a description before you post. Video descriptions work the same way as alt text on X, and they cannot be added after the fact.
4. Add text and post.

Uploads process after they finish transferring, so a long video sits in "processing" for a while before the post button becomes usable. Do not close the composer during that window.

#Length that works versus length that is allowed

The 125-minute ceiling is a capability, not a recommendation. Two hours of video on X competes against a feed built for scrolling, and completion rates fall off a cliff long before the file does.

What holds up in practice:

• Under 30 seconds for anything meant to earn replies. It plays and finishes before someone flicks past.
• 1 to 3 minutes for a demo, a walkthrough or a clip with a real point. Long enough to say something, short enough to survive.
• Anything longer needs a reason a viewer already trusts you, which usually means an audience that came for you, not for the algorithm.

Two habits raise video performance more than resolution ever will. Open on motion or a visible claim in the first second, because autoplay is muted and silent frames read as nothing. And burn captions into the video rather than relying on the player, since most people watch without sound.

If video is part of a monetisation plan, note that X pays on engagement from other subscribers rather than on raw views, which we broke down in how much X pays for views. Video reach and video revenue are not the same lever.

#Getting video into a posting routine

Video on X has an awkward truth attached: the hard part is not the specs, it is showing up with a clip often enough for the format to compound. A video every few weeks between long silences performs like a video from a stranger.

Batching solves the production side. Record three or four short clips in one sitting, export them all as 720p MP4, and queue them: how to schedule posts on X covers the free and paid routes for that. Scheduling does not touch the other half of the job, which is being present in replies while the video is live and earning its early engagement. That is the layer X-Autopilot handles from your own machine.

Get the encoding right once, save the export preset, and the specs stop being something you think about at all.