Everyone knows bitrate matters, but do you know why? A simple definition is fine, but to truly optimize your stream and understand why your video looks the way it does, you need to go deeper. This post breaks down bitrate into three clear parts, providing a detailed, practical understanding of its function and why it matters to your audience.
Data by the Dot
Converted to Code
Specifically for a Second
Putting It All Together
Final Thoughts
A bit is the smallest unit of data in computing, representing either a 0 or a 1. A byte is slightly larger, made up of 8 bits grouped together. Scale things up and you’ll typically find larger denominations of data use “byte” as an ending rather than “bit”: kilobyte (about 1,000 bytes), megabyte (about 1,000 kilobytes), gigabyte, terabyte, petabyte, and so on.
The word we’re focused on here, though, always uses “bit” because bitrate measures data at the smallest specific level, down to each individual dot. Since audio data is smaller than video, it has typically been measured in kilobits while larger video data almost always uses megabits.
If you think about it, we use different variations of measurement all the time based on the typical amount needed or used. Gasoline and milk are both measured and sold in gallons while gold and other precious metals are measured in troy ounces. When it comes to audio and video streaming, measuring down to the very bits help keep things specific to ensure optimal presentation.
Bitrate is a term that always applies to digital media. More specifically, it refers to data that is converted from a raw format into a digital one through a process called encoding. This conversion prepares the audio or video data to be sent, whether it’s being streamed, stored, or shared.
Encoding can be done in several ways, either through software or with a dedicated hardware device known as an encoder. No matter how it’s done, the process of turning data into a structured digital format is essential for practical distribution and playback at a specific bitrate.
We’ve already talked about kilobits (Kb) and megabits (Mb). Building on that, let’s look at Kbps and Mbps, which stand for kilobits per second and megabits per second. These are the most common units used to measure data transfer speed.
The higher the amount of data that needs to be transferred, the more you’ll need efficient compression, an effective protocol, or a faster internet connection. The reason is simple: it takes more effort to move a larger volume of data bits every second to achieve higher quality content.
In live streaming, for example, you’ll typically need around 4 Mbps to stream in 720p HD, about 8 Mbps for 1080p, and 12 Mbps or more for 4K content. For audio, standard quality might require 256 Kbps, while high fidelity audio may need 320 Kbps or higher. The higher the quality of your video or audio, the more power and bandwidth are required to deliver it clearly and consistently.
We now have a brief yet specific understanding of the term bitrate:
This definition can also be adjusted to apply to either medium individually:
“Video bitrate is the amount of data used to encode one second of video.”
"Audio bitrate is the amount of data used to encode one second of audio."
Now that you have a clear understanding of bitrate and how it applies to both video and audio, it’s worth knowing that your bitrate can still face challenges. Even if you’re sending data at a steady rate, issues can arise when your network can’t keep up and data packets begin to get lost.
To keep your stream stable, there are steps you can take to overcome these challenges. Many of them come down to how you stream — specifically, the streaming protocol you use. If you want to ensure that your bitrate can hold steady even when network conditions fluctuate, we encourage you to learn more about the most resilient and reliable streaming protocol on the market here. Additionally, check out our blog on “Is a higher bitrate always better?” for further reading on this subject.