The Complete Guide to Understanding Video Aspect Ratios

Do you remember about a decade ago when DVDs came with the option of widescreen or full-screen viewing options?

You probably noticed that if you chose the wrong option, parts of the movie were either cut off or the video had too much black padding around it.

The standard size of television screens was stretching from a 4:3 width to height ratio to one that was much wider. Producers began to make movies that would work for both screens.

Now that display aspect ratios are more standardized, broadcasters and content creators pay close attention to the video aspect ratio or the width to length ratios of their videos.

Professional audio, sharp visuals, perfect lighting, and other cinematic measures of quality are typically considered right off the bat, but aspect ratios are often a secondary conversation. 

The aspect ratio of your videos is something to keep in mind when creating and broadcasting video content for your audience.

Today, we are going to break down what exactly video aspect ratios are, commonly used ratios, and video resolutions, as well as the role they play in live video streaming.

Table of Contents:

• What is Video Aspect Ratio?
• Aspect Ratio and Resolution
• Common Aspect Ratios and Their Uses
• How to Tell the Aspect Ratio of a Video
• What is the Best Aspect Ratio for a Video?
• How to Change the Aspect Ratio of a Video
• Video Aspect Ratios in Live Streaming
• Aspect Ratios in Your Video Creation

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What is Video Aspect Ratio?

The video aspect ratio indicates the orientation of a video by providing the ratio of width to height as measured in pixels.

The numbers that appear in the ratio are not necessarily representative of the height and width in terms of pixels (px). It is just the ratio between width and height. 

For example, a video with a 16:9 aspect ratio would not be 16 px wide and 9 px tall. You wouldn’t be able to see a video that small. One resolution that has an aspect ratio of 16:9 is 1920 px by 1080 px.

Aspect Ratio and Resolution

For every aspect ratio, there are several counterpart resolutions. Aspect ratio and resolution go hand-in-hand.

To get the resolution, you would multiply the width times the height. Whereas, to get the aspect ratio, you divide the width by the height.

By multiplying the width times the height, you get the number of square pixels on the screen. The higher the number the better in terms of video quality.

There may be times when opting for lower quality is the way to go. A lower-quality video would be of benefit if you’re in need of smaller file sizes. In these instances, you would record your video at the highest HD streaming quality and use encoding software to make lower-resolution copies of the video.

Common Aspect Ratios and Their Uses

There is no one-size-fits-all when it comes to video aspect ratios. Aspect ratios are typically chosen based on where the video will be posted, how it will be viewed, and what purpose it serves.

Videos used for social media will vary from movies or trailers that are shown in theaters. There are standard aspect ratios for modern televisions, but broadcasters are free to use the aspect ratio that works best with their content and audience.

Since most videos are broadcasted through standard online video platforms, custom aspect ratios are not commonly used.

Here are a few common aspect ratios that you can use for live streaming and other video creation:

16:9

A video with a 16:9 aspect ratio is a wide rectangle. It is also often referred to as “1.71:1” which is the most simplified form of the ratio, mathematically speaking.

Today, you’re likely to use the 16:9 aspect ratio for most of your video creation and streaming since the 16:9 ratio is considered the international standard format for television, cinema, and major online streaming setups and platforms.

Since this aspect ratio is so popular, many tend to use it when they live stream on their own sites, as well.

16:9 is the default setting on most video capture devices, both professional-grade and consumer-grade. It also is the most common size for video players.

There are a few reasons that 16:9 has become the norm. Screens of this size provide higher resolution than those with aspect ratios of 16:10, which used to be considered the international standard. 

It is also more cost-effective to create screens that are compatible with this ratio as opposed to their predecessors. The standardization of both televisions and computer monitors saved producers time and money in the research arena. 

One of the best resolutions you can hit with a 16:9 aspect ratio is 4K or 3840 px by 2160 px.

1:1

The 1:1 video aspect ratio is a perfect square and was originally used with square television sets.

Today, the 1:1 aspect ratio is much less commonly used. You’re most apt to find it on social media platforms such as Instagram or Facebook.

While it is not the most commonly used aspect ratio, many cameras still have a square setting. 

4:3

Before 16:10 and 16:9, the 4:3 aspect ratio was standard for traditional television and computer monitors. The reason for the switch was the birth of HDTV. The 16:10 and 16:9 aspect ratios allow for greater resolutions than 4:3 do.

This aspect ratio was still used for Apple iPads until their release of the 2018 iPad Pro. The 4:3 aspect ratio is being phased out, so it is not very common.

3:2

The 3:2 aspect ratio was originally used for classic 35 mm still photography. It is still used on some laptops, tablets, and handheld game consoles. 

Many micro- to medium-sized cameras still have the 3:2 aspect ratio settings, but it is rarely used by broadcasters today.

21:9

The 21:9 aspect ratio has a very particular purpose. It is often referred to as ultra-widescreen or cinematic widescreen.

It is used for films with an anamorphic format. Anamorphic format videos are used to create an optical illusion that provides a 360-degree view.

You are likely to find videos with this aspect ratio in special theaters, museums, theme parks, and the like. They are designed to give more immersive experiences to the viewers. 

The illusion caused by screens of this dimension is intended to feel like you’re in the video rather than watching the video.

9:16

A 9:16 aspect ratio is used for tall videos. This aspect ratio became popular when smartphones were created with video capabilities.

For example, the optimal measure for an Instagram story is 1080 px by 1920 px, which means its ratio is 9:16. The same goes for other popular apps that have “story” features, including Facebook and Snapchat. 

This makes sense because the iPhone camera’s video setting can record footage in both 9:16 and 16:9.

How to Tell the Aspect Ratio of a Video

Most cameras with video capabilities come with a variety of aspect ratio settings. This allows you to decide which aspect ratio you’d like your video to have before you record it.

If you are trying to tell the aspect ratio of a video that has already been filmed, you can access additional information for the file. On Macs, the information button is a small “i” in a circle. On PCs, you right-click a file and click “Properties.”

It may give you the actual width and height of the video, but you can divide the two to find the aspect ratio.

What is the Best Aspect Ratio for a Video?

The most common aspect ratio for videos is 16:9. However, this does not make it the best aspect ratio.

The reason that it is so popular is that it is the standard for high definition televisions and popular streaming platforms like Dacast, Brightcove, Youtube, TikTok, or Netflix.

A 16:9 ratio is typically seen as optimal because it is capable of the highest resolution. It is also easy to capture this aspect ratio on almost all devices. 

To determine which video aspect ratio is best for your content, consider its purpose and where you’ll be broadcasting the video.

How to Change the Aspect Ratio of a Video

There are two ways to change your video’s aspect ratio: add black bars around your video or crop it.

While it’s totally possible to change the aspect ratio of your video after it has been filmed, it is not always recommended. This is because both methods have their downfalls.

If you want to go the route of cropping your video, you need an editing tool that has cropping capabilities. 

Whether your goal is to make the video taller or wider, cropping could cut important people or objects out of the frame. You may be forced to choose which parts of the frame are the most important and lose the rest.

Adding black bars as an alternative to cropping your video, is great in the sense that it keeps the full video. The downside? The black bars aren’t necessarily the most appealing.

Depending on where you’re broadcasting the video, your content may be edited automatically. For example, the aspect ratio of YouTube videos is 16:9 aspect ratio as the platform adds white padding around all videos to make them fit. However, other social media platforms will crop your videos to fit their set aspect ratio.

Video Aspect Ratios in Live Streaming

Live broadcasts are tricky in the sense that you have to figure out the logistics before you film since your audience consumes the content as it’s created.

The video aspect ratio you choose for your stream must follow video streaming protocol, which demands two things: universal playback and small file size.

With the 16:9 aspect ratio, you can cross off both. There is a wide range of resolutions that you can choose from, so you are able to find the optimal resolution where the desired quality and file size meet.

Essentially any streaming device including computers, televisions, mobile devices, and HTML5 video players can play videos with a 16:9 aspect ratio, so universal playback is also guaranteed.

When you broadcast live, it is very important that you make sure that the video aspect ratio of your recording equipment is compatible with the streaming platform of your choice. You don’t want anything important to be cut out, especially since you won’t have the chance to reshoot the content.

Aspect Ratios in Your Video Creation

Aspect ratios—the ratio between the width and length of your video—are certainly something to consider when producing video content to broadcast to your audience.

While the compatibility of the video aspect ratio and your video hosting platform or streaming service is of great importance, you have to keep the user experience in mind.

Think about the type of devices that more viewers will use to watch your videos, and make your decision accordingly.

Whether you choose a standard 16:9 aspect ratio for content to be streamed on a laptop or a 9:16 ratio to be streamed on a cell phone, make sure it presents clearly without untasteful cropping so that your audience has the best experience.

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