Subtitles and closed captions play an important role on your viewers outreach and SEO.
While it gives access to a larger audience (e.g. viewers who need the subtitles due to being hard of hearing or not knowing your language), it also has an impact on how easy it is to find your videos on search engines like Google.
The Google developers documentation says that search engine optimization, or SEO, "is the process of increasing the visibility of website pages on search engines in order to attract more relevant traffic".
This means that a good SEO is important for your video to be found on Google.
Let's say a potential viewer is searching for a content that you already made a video for. For example, let's say you have a video titled "How to cook Quesadilla".
If your potential viewer searches for "How to cook quesadilla" on Google, they will find this as the top results:
As you can see, there is a video on the top, with the title "How To Make The Perfect Quesadilla". The reason that video is on the top result is it has a high SEO score.
Notice that the first variable on the list above has the word content in it. Content in the context of the video is what is being said in the video.
This is basically the video transcript, which can be created by adding subtitles to it. The more keywords and better content your video offers, the better will search engines rank your video.
While subtitles and closed captions help your video's SEO by being ranked up in search engines, adding captions also helps you reach a much bigger audience.
The reasons a captioned video may reach a broader audience vary. Not only will your video be accessible to people who can't understand your language, but also to people who are hard of hearing, or want to play the video on mute, or just like subtitles in general.
A recent research made by Netflix shows that "more than 80% of members use subtitles or closed captions at least once a month, with many of them reporting that they use dubs and subtitles to learn new languages. In the last two years, US viewing of non-English titles has increased by 33%."
This is proof that subtitles are required for many users to have access to your video. Without captions, many would not watch the video and help with your views count.
Subtitles and closed captions benefit you and your fans in multiple ways. Adding captions will help you rank better on search engines and also reach a bigger audience.
If you still haven't decided wether you should add subtitles to your videos, you can also consider asking your fans to help you with a platform like Captionfy. Community captions can speed up the process and engage your audience in a positive way for everyone involved.