How to Add Subtitles to X (Twitter) Videos

On X, videos autoplay on mute. Many viewers scroll through with no soun.

If you’re wondering how to add subtitles to your X videos the right way, you’re in the right place.

In this guide, you’ll learn what subtitle format works best on the platform and how to generate them.

Does X (Twitter) Have Auto-Caption for Videos?

If you post a video on X (formerly Twitter), will it generate subtitles for you?

The short answer is no.

X does not offer automatic captioning for videos. There’s no built-in speech recognition, no automatic transcription, and no toggle to add subtitles directly in the app.

What Happened to Auto-Captions?

In the past, X experimented with limited caption support. However, automatic captioning never became a stable feature on the platform.

Some users hoped for built-in tools like those on TikTok or Instagram. But instead, X kept things simple — offering a way to upload external subtitle files during video publishing.

As of now, there’s no automatic subtitling at all.

What Are Your Options?

Since there’s no built-in auto-caption tool, you have two main options:

1. Upload a subtitle file (like an .srt) when posting your video
2. Burn the subtitles into the video before uploading — so they’re always visible

What Subtitle Formats Are Supported by X (Twitter)?

If you’re ready to upload a video to X (formerly Twitter) with subtitles, you need to know what formats work.

X supports only one official subtitle format: .srt (SubRip Subtitle).

That’s it. No .vtt, .ass, or .sbv. Just .srt. So if your subtitles are in a different format, you’ll need to convert them before uploading.

How to Add an .SRT File When Posting a Video

When you upload a video to X, you’ll have the option to add a subtitle file. Here’s how:

1. Start a new post as usual
2. Click the media upload button and select your video
3. Look for the option to upload subtitles
4. Choose your .srt file from your computer
5. Complete your tweet and publish

Your captions will now be available to viewers who have closed captions enabled.

Note: This option may only be available through X’s Media Studio or for users with professional accounts. If you don’t see it in the mobile app or standard web composer, try using the Media Studio dashboard instead.

Things to Keep in Mind

When preparing your .srt file, make sure:

• The timing matches your video exactly
• Each subtitle line is short and readable
• Your file is saved with UTF-8 encoding, so all characters show up correctly
• The filename is clear and easy to find — like video-subtitles-en.srt

What If You Need Multiple Languages?

X doesn’t support toggling between subtitle languages. You can only upload one subtitle file per video.

So if you want to post subtitles in another language, you’ll need to:

• Create a separate .srt file
• Upload it with a separate version of the video

Or you can burn the subtitles into the video using different language versions.

How to Generate Subtitles for X (Twitter) Videos Using Checksub

Creating subtitles manually for your X videos can be frustrating. It takes time. You need to type out every word, sync the text to the audio, and format the file just right.

That’s why tools like Checksub exist — to make it easy, fast, and accurate.

With Checksub, you can generate subtitles automatically using AI. Then you can export your subtitles in the correct .srt format — ready to upload with your X video.

Here’s how to do it.

Step 1: Generate Subtitles

First, go to checksub.com and log into your account. If you don’t have one yet, creating it only takes a few seconds.

Click “Upload Video” and choose your file. Checksub accepts all major formats like .mp4, .mov, and .mkv.

After uploading, select the original language of the video. You can also choose additional languages if you want to create subtitles for an international audience.

Once your video is uploaded, Checksub’s AI automatically transcribes the audio.

In just a few minutes, the tool will:

• Transcribe the speech with high accuracy
• Break the dialogue into readable subtitle lines
• Time each subtitle to match your video perfectly

You’ll get a full subtitle track — without typing a single word.

Step 2: Review and Edit

Once the transcription is ready, you’ll be taken to the subtitle editor.

This is where you can:

• Review the text and fix any small errors
• Merge or split lines for better readability
• Add speaker names or sound effects if needed
• Make sure each subtitle fits naturally with the flow of your video

Checksub also helps you stay within ideal reading limits — so your captions are short and easy to follow.

Want your subtitles to match your brand?

Checksub lets you adjust:

• Font type and size
• Text color and background
• Line spacing and position

If you’re planning to burn subtitles into your video, these styling options are key.

If you’re just exporting an .srt file for X, the visual style won’t transfer — but the clean formatting will still help ensure readability.

Step 3: Export Your .SRT File

When everything looks right, click “Export” and choose the .srt format.

Now your subtitle file is ready to upload alongside your video on X.

X Subtitles Troubleshooting — Common Issues and How to Fix Them

You’ve created your subtitles. But something’s not working.

Don’t worry — here’s how to solve the most common issues when adding subtitles to your X (Twitter) videos.

1. Subtitles Not Displaying

If your captions aren’t appearing after upload, here are a few things to check:

• File Format: Make sure you uploaded an .srt file. X doesn’t support .vtt, .ass, or other formats.
• Encoding: The subtitle file should be saved in UTF-8 encoding. If not, special characters may break the file.
• Structure: Every line in your .srt must follow the correct format — number, timestamp, then text. Missing or extra line breaks can prevent the file from working.

Example of correct formatting:

pgsql

CopierModifier

1
00:00:00,000 --> 00:00:03,000
Welcome to the video!


If any lines are missing numbers, timestamps, or spacing, subtitles may not load.

2. Captions Are Out of Sync

Are your subtitles showing up too early or too late?

That usually means the timestamps don’t match the audio.

Here’s how to fix it:

• Use a subtitle editor like Subtitle Edit, Aegisub, or even Checksub to shift the timing.
• Adjust the start and end times of each line until everything matches the speech.
• Re-export the corrected file and upload it again.

Even small changes in video duration can throw off sync — so double-check the final version you’re using.

3. Can’t Find the Subtitle Upload Option

Not everyone sees the subtitle upload tool when posting videos. Here’s why:

• It may be available only in Media Studio, which is part of X’s professional tools.
• If you’re using the standard tweet composer, the subtitle upload feature might not appear.
• Try switching to a desktop browser or logging into studio.twitter.com to manage your media and add captions.

If you still can’t find it, consider embedding (burning) your subtitles directly into the video before uploading.

4. Embedded Subtitles Not Showing

If you’ve burned the subtitles into your video but they don’t appear:

• Double-check that you exported the video correctly — with hardcoded subtitles
• Make sure the text is clearly visible (good contrast, proper size)
• Test playback on both desktop and mobile — some devices display video differently

If everything seems right but captions still don’t appear, try re-exporting or previewing the video in a different media player.