Aspect Ratio & 16:9 Aspect Ratio: A Comprehensive Guide to Aspect Ratios in Video Technology

In the world of video, the “aspect ratio” plays an important role in the presentation and quality of your visual content. Aspect ratio refers to the proportional relationship between the width and height of an image or video.

Your video’s aspect ratio affects the way it fits on the screens of different devices, influencing how your audience experiences your content.

In this article, we will dive deep into aspect ratios, with a particular focus on the 16:9 aspect ratio. By the end, you will have a complete understanding of what aspect ratios are, how they’re calculated, the different types available, and the significance of the 16:9 aspect ratio.

What is an Aspect Ratio?

Aspect ratio refers to the proportional relationship between the width and height of an image or video. It’s expressed as a ratio, for example, 16:9 or 4:3, and represents the number of horizontal units to the number of vertical units. In other words, the first number represents the width, while the second number represents the height of the video.

The aspect ratio has a significant impact on how a video appears on a screen, dictating the dimensions and shape of the display.

aspect ratio and 16:9 is an important concept in video technology
Photo by Tim Mossholder on

How Aspect Ratios Are Calculated

Calculating aspect ratios is not a difficult process and you can do it easily, provided you know the width and height of the image (or video).

To calculate the aspect ratio, go ahead and divide the width of an image or video by its height. This results in a decimal, which can be converted into a ratio by finding the smallest whole numbers that have the same ratio.

For example, if a video has a resolution of 1920×1080 pixels, the aspect ratio is 1920 ÷ 1080 ≈ 1.778. This value is then expressed as a ratio of whole numbers, 16:9 in this case, which is the same proportion.

Wasn’t it simple? Now, let’s learn about some popular aspect ratios used in the video industry.

common aspect ratios used in video streaming
Common Aspect Ratios. Credit: Wikimedia

Different Types of Aspect Ratios

There are several aspect ratios that have been used in the history of video and film. Some of the most common include:

  1. 4:3
    • Also known as the standard or classic aspect ratio, 4:3 was widely used in television and computer monitors before the advent of widescreen displays.
    • Films produced before the 1950s typically used this ratio.
    • This aspect ratio has a width that is 4/3 times the height.
    • For example, a video with a width of 640 pixels and a height of 480 pixels has a 4:3 aspect ratio.
  2. 16:9
    • The most popular aspect ratio in modern video technology, 16:9 is the default standard for HDTV, digital video, and widescreen television.
    • It’s also used in many smartphones, tablets, and computer monitors.
    • This aspect ratio is used in high-definition videos, such as Blu-ray discs and almost all popular streaming services like Netflix and YouTube.
    • A video with a width of 1920 pixels and a height of 1080 pixels has a 16:9 aspect ratio.
  3. 1.85:1
    • Often referred to as widescreen or flat ratio, 1.85:1 is common in American cinema.
    • This ratio is similar to 16:9 and works well on widescreen displays.
    • This aspect ratio is used to provide a wider and more immersive viewing experience for the audience.
    • A video with a width of 1663 pixels and a height of 900 pixels has a 1.85:1 aspect ratio.
  4. 2.39:1
    • Also known as CinemaScope or anamorphic widescreen, 2.39:1 is a popular aspect ratio in the film industry.
    • This ultra-wide format provides a more cinematic look and is used extensively in movies.
    • A video with a width of 2048 pixels and a height of 858 pixels has a 2.39:1 aspect ratio.
  5. Non-Standard Aspect Ratios
    • Apart from the standard aspect ratios, there are also non-standard aspect ratios that are used in video production.
    • These aspect ratios are usually used to create a specific effect or to fit a particular display.
    • For example, a video with a width of 1280 pixels and a height of 512 pixels has a 2.5:1 aspect ratio, which is a non-standard aspect ratio.

I hope that by now, you have a fairly good understanding of aspect ratios, how they are calculated, and the most common aspect ratios that you see in video technology.

Now, let’s learn more about the most popular aspect ratio in online video streaming, which is, the 16:9 aspect ratio.

Understanding the 16:9 Aspect Ratio

The 16:9 aspect ratio has become the most widely used aspect ratio in modern video technology and video streaming. You can see its use in almost every video streaming platform like YouTube, Hulu, Amazon Prime, SonyLIV, and more.

Here are some of the most popular 16:9 video formats used in the industry along with the corresponding dimensions (width x height).

  • 4320p (8k): 7680×4320 pixels
  • 2160p (4K): 3840×2160 pixels
  • 1440p (2k): 2560×1440 pixels
  • 1080p (HD): 1920×1080 pixels
  • 720p (HD or full-HD): 1280×720 pixels
  • 480p (SD): 854×480 pixels
  • 360p (SD): 640×360 pixels
  • 240p (SD): 426×240 pixels

You’ll probably recognize these resolutions off the bat, as they are so popular in online video streaming. Here is an example from YouTube’s video quality setting.

video resolutions
Video resolutions that YouTube uses for its online video streaming. Recognize the 16:9 aspect ratio?

And this is what Google has to say – it clearly pushes you to use 16:9.

The standard aspect ratio for YouTube on a computer is 16:9. If your video has a different aspect ratio, the player will automatically change to the ideal size to match your video and the viewer’s device. 

For some video and device aspects ratios like 9:16 vertical videos on computer browsers, YouTube may add more padding for optimal viewing. The padding is white by default, and dark gray when Dark theme is turned on.

Let us take a closer look at why it has become so prevalent and its applications in various media.

Related:  3 Things Every Broadcaster Should Know to Succeed with Digital Video in 2021

Why is 16:9 so Popular?

History and Adoption

The 16:9 aspect ratio was introduced in the 1980s as a compromise between the traditional 4:3 television ratio and the wider aspect ratios used in cinema. It was created to provide a more immersive viewing experience, allowing for more content to be displayed on screen. The International Telecommunication Union (ITU) designated 16:9 as the international standard for HDTV, paving the way for its widespread adoption.


The 16:9 aspect ratio is commonly used in digital video, television broadcasts, video games, and online streaming platforms. It’s also the standard for most smartphones, tablets, and computer monitors, making it ideal for content creators who want their videos to be displayed correctly on various devices.

The increased width of 16:9 aspect ratio enables content to fill the screen and be displayed without black bars on the sides or top and bottom. This also makes it an excellent choice for content that benefits from a wider field of view, such as landscape shots, action sequences, or panoramic images.

Compatibility with Other Aspect Ratios

One of the reasons the 16:9 aspect ratio has become so popular is its compatibility with other common aspect ratios. When content created in 4:3, 1.85:1, or 2.39:1 aspect ratios is displayed on a 16:9 screen, it can be easily adapted with minimal loss of visual information.

This is typically achieved by adding black bars (letterboxing or pillarboxing) or, in some cases, stretching or cropping the content to fit the screen.

If you want to learn more, here is a great video on Letterboxing on YouTube.

letterboxing when changing aspect ratios
Letterboxing – black bars on top and below the image. Credit: Wikipedia

Use Cases for the 16:9 Aspect Ratio

The 16:9 aspect ratio is used in various types of videos, including movies, television shows, commercials, and online videos. It is the standard aspect ratio for high-definition videos and is used by most online video platforms, such as YouTube and Vimeo.

Movies and Television Shows

The 16:9 aspect ratio is commonly used in movies and television shows. Most modern televisions have a widescreen display that is compatible with the 16:9 aspect ratio. The 16:9 aspect ratio provides a more immersive viewing experience for the audience and is particularly suitable for movies that require a cinematic effect.


The 16:9 aspect ratio is also commonly used in commercials. Commercials are often created in high-definition video and are designed to be viewed on a wide range of devices, including televisions, smartphones, and tablets. The 16:9 aspect ratio provides a consistent viewing experience across different devices and is compatible with most modern display technologies.

Online Videos & Live Streaming

The 16:9 aspect ratio is the standard aspect ratio for most OTT (VOD or LiveStreaming) video platforms, such as YouTube and Vimeo. This is because the 16:9 aspect ratio is compatible with most modern devices, including smartphones, tablets, and laptops and offers a uniform experience from the content creator to the end user.

What Aspect Ratio should I choose for my Live Streaming Project?

Now that you understand aspect ratios and the prominence of the 16:9 ratio, how do you decide which aspect ratio is right for your VOD or live streaming project?

Here are a few factors to consider:

  1. Target Audience: Consider the devices your target audience is likely to use when viewing your content. If your audience primarily uses modern devices like smartphones, tablets, or widescreen televisions, the 16:9 aspect ratio is a solid choice.
  2. Visual Style: Think about the visual style you want to achieve with your project. If you’re aiming for a more cinematic look, you might opt for a wider aspect ratio like 2.39:1. However, if you want a more traditional or intimate feel, the 4:3 ratio could be a better fit.
  3. Distribution: Consider the platforms where your content will be distributed. Online streaming platforms and HDTV broadcasts often favor the 16:9 aspect ratio, while cinema releases may prefer a wider aspect ratio.
  4. Compatibility: Be aware of how your chosen aspect ratio will appear on different screens. While the 16:9 aspect ratio is versatile, it may not always be the best choice for every project. Select the aspect ratio that will display your content correctly and provide the best viewing experience for your audience.

Also, take a look at what others are using (your colleagues or competitors) and that will give you a good idea about the right aspect ratio to choose for your next project.


Aspect ratio is an essential element of video production that can affect the overall quality of the video. It is the proportional relationship between the width and height of an image or video and is expressed in two numbers separated by a colon.

The 16:9 aspect ratio is the most commonly used aspect ratio in video production today and has become the defacto-standard aspect ratio for online streaming services like Netflix and YouTube. The 16:9 aspect ratio is suitable for most types of videos and is compatible with most modern devices.

However, there may be situations where a different aspect ratio is more appropriate. By understanding the different types of aspect ratios and their uses, you can choose the right aspect ratio for your video and ensure that it looks its best on any device.

Until next time, happy streaming.

krishna rao vijayanagar
Krishna Rao Vijayanagar

Krishna Rao Vijayanagar, Ph.D., is the Editor-in-Chief of OTTVerse, a news portal covering tech and business news in the OTT industry.

With extensive experience in video encoding, streaming, analytics, monetization, end-to-end streaming, and more, Krishna has held multiple leadership roles in R&D, Engineering, and Product at companies such as Harmonic Inc., MediaMelon, and Airtel Digital. Krishna has published numerous articles and research papers and speaks at industry events to share his insights and perspectives on the fundamentals and the future of OTT streaming.

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