How the TikTok Algorithm Works

A detailed look at the science behind how the TikTok algorithm works. Also includes tips on how to create engaging video content that has a better chance at going viral.

UNUM Staff

Everyday Social Tool

Zach King's Harry Potter illusion video gained 2.2 billion views awarding him the title for the most viewed TikTok of all time. People everywhere found themselves fascinated by his video where he shares how he found a way to be a wizard even though his application to Hogwarts was rejected.

As a culture, we are attracted to the unexpected and random nature of this type of content which is fresh and never boring. 

Zach King on TikTok

Today everyone is going nuts over these bite-sized video clips infused with unique sounds, popular music, and filters. TikTok, which has been rapidly growing in popularity since its inception in September of 2016–reaching 1.2 billion active monthly users in 2021–is now dominating social media. Teenagers and adults alike have become addicted to watching these interactive videos, which leaves you wondering—what is the science behind this fascinating social giant? 

How it works 

The TikTok algorithm is not as mysterious as it may seem. There are many factors that come into play such as hashtags, location, music choices, and previously “liked” videos. So how are videos selected that are specifically targeted for you in the ever-popular #ForYou feed? According to TikTok, the system recommends content by ranking videos based on factors such as things you have expressed interest in. 

As explained by TikTok: 

"When you open TikTok and land in your ForYou feed, you're presented with a stream of videos curated to your interests, making it easy to find content and creators you love. This feed is powered by a recommendation system that delivers content to each user that is likely to be of interest to that particular user."

The key drivers

According to the consumer tech and lifestyle communications agency Ranieri, TikTok is using machine learning to evaluate the quality of every video uploaded. Because TikTok only shows videos to a small number of users, the users don’t get bored. The algorithm measures how much a video is watched, as well as how many likes, comments, and shares it gets, and the viral videos hook in users and make them want to watch more.

Some of the main factors that define which of these videos users see in their feed include:

  • User interactions: TikTok factors in the videos that you like and share, the accounts you follow, the content you create, and the comments you post. If you post using certain hashtags, you are very likely to see content with those same hashtags in your feed. 

  • Video information: This could include captions, song choice, sounds, and hashtags that you use. 

  • Device and account settings: Your location, language preference, and mobile device type are also taken into consideration, but not as much as the other factors above. 

Creating a viral video

According to Hootsuite, the following are some of the key tips that you should incorporate into video making that will increase your engagement, followers, and ranking:

  • Create short, 15-second videos that are well-edited.

  • Create video content that engages from the start. (Perhaps catch their attention with something unexpected.)

  • Add engaging captions. 

  • Post at times when your audience is the most actively engaged: In order to really hone in on your analytics, you may want to consider investing in a TikTok Pro Account. From the Analytics tab, you’ll be able to find the “Follower Activity” section which will provide information on when your audience is the most active, and help you figure out the best times to post. 

  • Engage with other TikTok users: One of the most popular ways to do this is by hosting a branded hashtag challenge, which is where a brand asks people to perform a certain task and they tag them using a specific hashtag. Other great ways to engage include commenting on videos, and sharing other’s content. 

  • Use fun and engaging sounds and music. (Note: even though the site rose to popularity largely with users dancing to popular songs, technically, these songs are still copyrighted and protected. According to Tech Junkie, it’s widely known that TikTok has struck deals with record labels. But, be forewarned. Excessive use of copyrighted music (or other copyrighted material) could open you up to account suspension. Or minimally, those videos could be taken down.)

  • Make sure that people can share your content on other social channels.

Most importantly, make sure that you are using the correct hashtags that are trending.

Serving up content 

The TikTok algorithm is designed to ultimately show you more of the content that you like because it’s based on your activity and interests. Although it is not an exact science, marketers may be able to better maximize their videos by having a greater understanding of how the platform works. According to Social Media Today, it is essential to note that videos count independently. Aligning with trending interests helps you connect with more users, as well as having viewers watch your video clips to completion. 

TikTok has become enormously successful because people feed off of trends. It’s easy and convenient to use and can appeal to almost anyone--even those with a short attention span. Influencer Marketing statistics have shown that TikTok currently has the highest follower engagement rates per post than any other social platform. With those types of metrics, it will be exciting to see how the TikTok algorithm continues to grow and change as new behaviors are learned from the app.

Learn more about how UNUM can help you increase your TikTok social engagement and optimize your analytics.

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