The Complete Guide to Understanding Video Aspect Ratios

Understand Video Aspect Ratios Image

As the standards in screen resolution and screen size change, so too do aspect ratios. Various aspect ratios have been prominent over time. The old 4:3 was the standard ratio when standard definition was the norm. Now it is much larger as high-definition television and full HD picture quality comes as standard across TVs, computer screens and streaming services. For broadcasters and content creators, ensuring audiences receive optimal video quality and display resolution boils means getting the aspect ratio right.

However, the aspect ratio is commonly ignored. The audio, lighting, and attractive visuals often take center stage while aspect ratios are on the back burner. But this is a mistake because the aspect ratio should always be considered when trying to broadcast high-quality video content.

In this article, we cover precisely what video aspect ratios are. We discuss the most commonly used ratios, video resolutions, and their importance in live-streaming video content.

Table of Contents

  • What is the 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
  • Conclusion

What is the Video Aspect Ratio?

what is video aspect ratio

The video aspect ratio is the video width in proportion to the height of the TV screen. This ratio describes how wide your video is.

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 with an aspect ratio of 16:9 is 1920 px by 1080 px.

Aspect Ratio and Resolution

video resolution

Video resolution and aspect ratios play an important part in video production and broadcasting.

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

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

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

Sometimes, opting for lower quality is the way to go. A lower-quality video would be of benefit if you require smaller file sizes. In these instances, you would record your video at the highest HD streaming quality using encoding software to make lower-resolution copies of the high-definition video afterwards.

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 its purpose.

Videos used for social media and television shows will vary from movies or trailers watching movies 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 uncommon.

Common video Aspect Ratios

Different Video Aspect Ratios Side by Side for Comparison.

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


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 popular aspect ratio used, mathematically speaking.

For many, 16:9 is the only widescreen aspect ratio they can work with. 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 increasingly popular, many use it when they livestream on their sites, too.

16:9 is the default setting on most video capture devices, both professional-grade and consumer-grade. It’s also 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.


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.


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

This aspect ratio was still used for Apple iPads until they released the 2018 iPad Pro. The 4:3 aspect ratio is being phased out, so it is uncommon.


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.


The 21:9 aspect ratio display has a very high definition and 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.


A 9:16 aspect ratio is used for tall videos. This aspect ratio became the most popular aspect ratio 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

video aspect ratio comparison

Consider the user experience when choosing an aspect ratio. Choose one that is universally compatible.

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 most common aspect ratios and ratios.

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.

This aspect ratio is popular because it is the standard for high-definition televisions and is popular with Dacast, Brightcove, YouTube, TikTok, and 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

video aspect ratio settings

The correct video aspect ratio settings play an important role in video production and broadcasting.

There are two ways to change your video’s aspect ratio: add thin black bars all around a complete image in your video or crop it.

While it’s 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 entire screen of the video taller or slightly 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 because 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 standard aspect ratio of YouTube videos is a 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 streaming platform

The aspect ratio is a key success factor in your live streaming process since it will ensure the quality of your video content.

Live broadcasts are tricky because you need 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 can 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, you must ensure that the video aspect ratio of your recording equipment is compatible with your streaming platform. You don’t want anything important to be cut out, especially since you won’t have the chance to reshoot the content.


As we’ve detailed, aspect ratios are incredibly important for broadcasting video content. By utilizing the same aspect ratio options we’ve listed, you can optimize your video for your needs. Configuring the best, most standardized aspect ratios will help you deliver an exceptional viewing experience to your audience.

To summarize, opt for a 16:9 aspect ratio for video content streamed from a laptop and 9:16 for the millions viewing through mobile devices today. And ensure there are no cropping issues so your audience receives the best viewing experience possible.

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Harmonie Duhamel

Harmonie is a Senior digital marketer with over 6 years in the Tech Industry. She has a strong marketing and sales background and loves to work in multilingual environments.