What Are Video Subtitles? Common Formats and Best Practices

Video subtitles are text versions of the dialog, sound effects, and other audio elements in a video. They are usually displayed on the screen along with the video and are designed to make the video more accessible to a wider audience, including individuals who are deaf or hard of hearing, non-native speakers, or those who prefer to watch videos with the sound turned off (known as muted videos).

Subtitles can also be used to translate the audio into different languages, making the video accessible to a global audience. Video subtitles can be added to a video as an integral part of the production process, or they can be added later as a separate file that is synced with the video.

This is part of a series of articles about video optimization

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Why Are Video Subtitles Important?

Video subtitles are important for several reasons:

  • Accessibility: Subtitles provide a way for people with hearing disabilities to enjoy videos and understand what is being said.
  • Translation: Subtitles help people who do not speak the language of the video to understand its content.
  • Improved comprehension: Subtitles can help viewers who have trouble understanding the audio due to background noise, accents, or other factors.
  • Search engine optimization (SEO): Videos with subtitles are more easily discoverable on the Internet, helping increase their visibility and reach.
  • Global audience: Subtitles make it possible to reach a global audience and break down language barriers.


Video Subtitles vs. Closed Captions

Video subtitles and closed captions are both forms of text that are used to provide dialog or commentary for a video. However, there are some key differences between the two:

  • Purpose: Subtitles are typically used to provide a translation of the audio, while closed captions are intended to provide a transcription of the audio for accessibility purposes or entertainment.
  • Style: Subtitles are often positioned at the bottom of the screen and are intended to be read while the video is playing, while closed captions are often positioned near the relevant dialog and can include additional information such as speaker identification and sound effects.
  • Format: Subtitles are typically stored as separate files that are synced with the video, while closed captions are often embedded in the video itself.
  • User control: With subtitles, the user has the option to turn them on or off, while closed captions are typically always on and cannot be turned off.

Common Video Subtitle Formats

SRT Format

SubRip Text (SRT) is a widely supported and simple format for adding subtitles to videos. It consists of a plain text file that contains time codes for each subtitle, the text of the subtitle, and a sequence number indicating the order of the subtitles.

SRT files have a “.srt” file extension and are easy to create and edit, making them a popular choice for amateur video creators. The time codes in an SRT file specify the start and end times for each subtitle, and the text of the subtitle is placed between the time codes.

EBU-STL Format

The European Broadcasting Union Subtitle Transmission (EBU-STL) format is used by professional broadcasters and is designed for the transmission of subtitles over digital networks.

It is a more sophisticated format that provides support for multiple languages and character sets, and includes advanced features such as teletext-style graphics and background colors. EBU-STL files are typically more complex than SRT files and require specialized software to create and edit.

WebVTT Format

Web Video Text Tracks (WebVTT) is a newer format that is specifically designed for use on the web and is becoming increasingly popular. WebVTT provides plain text files that contain time codes for each subtitle and the text of the subtitle.

WebVTT files have a “.vtt” file extension and are designed to be easily parsed and processed by web browsers. These files are similar to SRT files, but support additional features such as styles and position information.

SSA Format

SubStation Alpha (SSA) is a subtitle format that is commonly used for anime and other animated content. It is a plain text format that provides a way to store and display subtitles in a video. SSA is a feature-rich format that supports a wide range of features, including custom styling, multiple languages, and the ability to display subtitles at specific times. This makes it a popular choice for fansubbing (creating subtitles for fans of anime and other animated content), as it provides a lot of control over the look and feel of the subtitles.

SSA subtitles are stored in plain text files that are synced with the video and displayed in real-time as the video plays. The format includes information about the timing, text, and appearance of each subtitle, which allows for precise control over the subtitles. SSA is supported by many popular video players and captioning software, making it a widely-used format for anime and other animated content.

4 Best Practices for Creating Video With Subtitles

Rules of Transcription

Here are industry standards recommended for creating videos with subtitles:

  • Legibility: The text should be easy to read and the font size should be large enough to be seen from a distance. It’s also important to choose a font that is clear and legible, especially for viewers with visual impairments.
  • Positioning: The text should be positioned correctly on the screen and should not overlap with other elements in the video. The position of the text should also be consistent throughout the video.
  • Synchronization: The text should be synchronized with the audio, appearing at the right time and for the right duration. This helps to avoid confusion and enhances the overall viewing experience.
  • Brief and clear: The text should be brief and to the point, avoiding unnecessary information or details that may distract the viewer. Clear and concise language is also important, especially for viewers who are not fluent in the language of the video.

Audio and Video Synchronization

Proper synchronization of the audio and video is critical for an enjoyable viewing experience. Here are key practices to consider:

  • Accurate time codes: To ensure that the subtitles are properly synced with the audio, it is important to use accurate time codes. Time codes specify the start and end times for each subtitle, and if they are incorrect, the subtitles may appear too early or too late.
  • Review the video: It is also important to carefully review the video to make sure that the subtitles appear at the right time and are synchronized with the audio. This can be done by playing the video and checking each subtitle to make sure that it appears at the right time and for the right duration.

Customizing Subtitles

Subtitles should be customized properly to ensure a good user experience. Here are some best practices to guide you through this process:

  • Font size: The font size should be large enough to be easily readable from a distance. It is also important to choose a font that is clear and legible.
  • Color and style: The background and text color should have appropriate contrast, making the text easy to read. The style of the text should also be consistent throughout the video.
  • Positioning: The position of the text should be consistent throughout the video, and it should not overlap with other elements in the video.

Subtitle Translations

If you are creating videos in multiple languages, it is important to ensure that the subtitles are properly translated and that the text is culturally appropriate for the target audience. If possible, it is best to use native speakers to translate the subtitles to ensure accuracy and cultural relevance.