How to Manually Edit a Captions (VTT) File on the WorkCast Platorm

Welcome to our blog on how to manually edit a VTT (Video Text Tracks) captions file on the Workcast platform. Captions are crucial for making videos accessible and engaging for all audiences, including those who are deaf or hard of hearing. In this blog, we'll guide you through the process of editing these files to ensure they accurately reflect the audio of your video.

Step 1: Open your captions file

To begin, you will need to open your VTT file in a plain text editor. If you're using a Mac, the built-in application TextEdit will work perfectly. For Windows users, Notepad is a reliable choice. Avoid using word processors like Microsoft Word, as they may add formatting that could corrupt your captions file.

Our Captions Management Insite page shows you how to download and upload caption files from the WorkCast platform. You can read it here.

Understanding the VTT file format

When you open your VTT file, you'll notice several components:

  • Text of the Captions: This is the actual spoken text from the video.
  • WEBVTT Header: This line indicates the file is a VTT file.
  • Sequence Numbers: Each chunk of captioning is preceded by a sequence number.
  • Timecodes: These are crucial. Each block of text has a starting and ending timecode, formatted as HH:MM:SS,MIL (hours, minutes, seconds, milliseconds).

Example of a typical VTT file section:


00:00:07.760 -> 00:00:10.180

I'll be telling you a little bit about the program.


This means the text "I'll be telling you a little bit about the program." will appear seven seconds into the video and disappear at ten seconds.

Step 2: Editing the caption text

Now, let's make some edits:

  1. Read and Type: Play the video alongside your text file. As you watch, read the captions and edit the text to better match what is being said or to correct errors. This could involve fixing typos, ensuring correct terminology is used, or adjusting the wording for clarity.
  2. Add Sounds: If there are significant non-speech audio cues (like [music], [applause]), add these in brackets at the appropriate places in the text.

What not to edit

  • Do Not Alter Timecodes unless the captions are appearing at incorrect times. Misaligned timecodes can lead to captions that are out of sync with the video.
  • Do Not Remove the WEBVTT Header or sequence numbers, as these are required for the VTT file to function correctly.

Step 3: Save and re-upload

Once your edits are complete, save your document. Ensure you maintain the .vtt file extension to prevent any file format errors. You can then re-upload this file to the Workcast platform or provide it to the vendor to upload.


Editing VTT files manually might seem daunting at first, but with a bit of practice, it becomes straightforward. This attention to detail not only enhances the quality of your videos but also improves accessibility, ensuring your content is enjoyed by a broader audience.

Whether you’re preparing for a webinar, a training session, or a product demo, accurate captions are essential. With this guide, you're now equipped to ensure your captions are as professional as your video content!

Happy editing, and remember—clarity and accuracy in captions not only comply with accessibility standards but also enrich the viewer experience, making your content more inclusive and engaging.


Get Email Notifications