Subtitling Vertical Videos: Guidelines, Where Art Thou?

If you use Snapchat or IGTV, you’re probably familiar with vertical videos. You probably haven’t considered them being in their own category before, though. If not, just grab your phone and have a look at this mesmerizing video of waves beating against a pier.


Example of a vertical video of Greta Thunberg encouraging us to save the planet, as seen on IGTV.

What’s the deal with vertical videos?

Vertical videos are intended to be viewed in portrait modethe image is taller than it is wider. The aspect ratio of most smartphones is 9:16 (although we can also find 9:18, 9:21, etc.). This format contradicts all past and current film-shooting strategies, where horizontal is king. Nowadays, the aspect ratio for TV sets is usually 16:9.

Still, the vertical format makes sense at least for social media and ads for smartphones. If you are scrolling down your timeline, you don’t want to turn your phone and watch a horizontal video, and then go back to the vertical position. It’s just not user-friendly.

Apart from Snapchat or IGTV, vertical videos can also be found on YouTube, Facebook, Twitter, and TikTok. Spotify has also started to create vertical music videos for its platform for users to watch while listening to music.


Example of a vertical video on Spotify

Even Netflix has joined the vertical video club, and now the preview mode on their smartphone app includes this format.

According to a study co-conducted by Buffer & Animoto, vertical videos perform better than square videos.

When analyzing Instagram Feeds, they found that vertical videos increased engagement compared to square videos:


Source: Buffer

In their co-authored report, Buffer found that vertical video resulted in a six percent increase of three-second video views and a 187 percent increase of 50 percent total watch time views, while Animoto found similar resultsvertical video resulted in a 13 percent increase of three-second video views and a 157 percent increase of 50 percent total watch time views.

Also, they advise businesses and brands to create more video content for mobile phones, which account for a great share of digital usage (65% in Q2 2018). Vertical videos are a great way to reach potential buyers. They are the most engaging format for that purpose, according to this study.

Can we subtitle vertical videos?

Of course, we can. They are being subtitled already in social media and Netflix preview mode, for example. But are the same subtitling rules that we use for horizontal videos still valid for vertical ones?

The space limitations are tighter in this format due to the aspect ratio of those videos. Therefore, current standards need to be revisited and updated.


Example of Netflix preview mode with subtitles from the film Tall Girl.

Current standards, revisited

Let’s take Netflix subtitle guidelines as a starting point:

  1. Duration: Subtitles should last a minimum of one second and a maximum of six seconds. This remains valid for vertical videos.
  2. Frame gap: Two frames should be left between subtitles. This remains valid for vertical videos.
  3. Line breaks: Two-line subtitles are the standard in the subtitling industry. There is enough space on smartphone screens (nowadays, mostly 9:16 or 9:18) to display the information even in the vertical position. Segmentation rules following semantic and grammatical rules such as breaking the line after punctuation marks, before conjunctions and prepositions, etc. should be maintained. 
  4. Position: Subtitles should be placed at the bottom of the screen. However, with vertical videos for marketing campaigns, creative solutions might be implemented with dynamic-positioned subtitles.
  5. Character limitation: There is not yet a standard for characters per line in vertical videos.

According to the BBC, the number of characters should not exceed 37 per line, with a maximum of two lines for TV. Even if that restriction might be somehow outdated for TV sets (for example, Netflix guidelines suggest subtitles have lines of up to 42 characters), it may work for vertical videos since the space is more limited. In some examples from Netflix preview mode that use vertical videos, subtitles with a length of 33 characters have been used without a proven negative impact on readability.

Guidelines on subtitling your vertical videos

Considering the lack of standards and after having a look at how media companies are implementing subtitles in this new format, we recommend the following guidelines for subtitling vertical videos:

  • Subtitles should have one or two lines maximum.
  • The character length per line should not exceed 37, depending on the font size. A safe area for subtitles in vertical videos needs to be established. On a screen, a safe area is a zone that can be seen. If subtitles are kept within the safe area, they will not be cut off.
  • Current segmentation rules must be kept.
  • If necessary, edited rather than verbatim subtitles should be used in order to comply with the character limitations. All information that is not essential for understanding the message can be cut out (for example, repetitions, redundancies, filler words, etc.).

Something you should consider is carrying out tests with subtitling users to define the safe area for subtitles in vertical videos and, then, the font size and the characters per line that can be used for subtitles to be comfortably readable.


Example of Netflix preview mode with subtitles from the series Cable Girls.

Why you should subtitle vertical videos on social media

If you need more convincing, let’s go over why subtitling vertical videos on social media should be seriously considered:

  • Videos on social media are usually watched without sound.
  • Ads in particular are mainly played on mute unless the viewer decides to turn the sound on. In fact, Google Chrome only allows autoplay for ads if the sound is automatically muted. Therefore, if you have a video marketing campaign on social media, you cannot forget to include subtitles because chances are that users will be watching your content without sound.
  • According to Paige Breaux from Skyword subtitling your videos will also make your brand more inclusive (for people with hearing impairments or non-native speakers), will improve comprehension and retention rates and will enhance your SEO strategy.

Moreover, a recent study showed that subtitled videos on Facebook had an average reach 16 percent higher than videos without subtitles.

Specific software for subtitling vertical videos

Now that you are convinced that you need to subtitle your vertical videos, the question is how. A couple of dedicated cloud-based solutions to add subtitles to vertical videos can be found online:

Also, apps such as Cliptomatic that use speech recognition are also a popular means to add subtitles for social media platforms, such as Instagram Stories.

Digital marketing and advertising is becoming more and more competitive. Brands are finding new ways of engaging their customers with user-friendly and eye-catching methods, such as vertical videos. Localizing your content is crucial to reach clients around the world. So don’t miss the train: climb aboard and adapt these best practices for subtitling vertical videos!



This article was researched and written by Belén Agulló García. If you wish to find out more about this topic, please reach out to Belén at [email protected].

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