Before we talk about bitrate, you’ll need to understand a few basic concepts. This is going to help you get an understanding of what bitrate really means and how to adjust it to an exact number for your setup and upload speed.
You may be tempted to just use the OBS wizard to generate your bitrate and other options but I would recommend avoiding this. It will be better for you to learn what your settings are actually do so that you may tweak them as needed!
Nibbles and Bits and Bytes
In computers, there are units of measurement to measure data. The same as there is the metric or imperial system to measure distance/speed. You are probably familiar with Kilobytes, Megabytes, Gigabytes and now the more familiar Terrabyte.
Keep in mind there are a lot more data sizes than just those four.
You can think of Byte as being the base or the zero of data sizes since anything smaller than a Byte is a fraction. Check out this table, keep in mind it doesn’t include every unit of measurement, you really don’t need to know more than bit, Kilobyte and Megabyte to understand bitrate.
Size in Bytes
|Nibble||4 bits||1/2 (rare)|
You can easily remember: 1 Byte = 8 Bits.
Upload Speed and Download Speed
Most of you will be familiar with the terms download speed and upload speed. However, we need quickly define them:
Download speed: the rate at which data is sent from a server/remote location to the users computer.
Upload speed: the rate at which data is sent from the users computer to a server. In our case, it’ll be an ingest server
UDP Speeds vs TCP Speeds
In computer networking, there are two protocols that determine how data is sent over the internet. In this article, we won’t be talking about them in-depth but you will need to know which one you’re using in order to use the correct upload speed test.
Mixer FTL = UDP – Testmy.net
Mixer RTMP/Twitch/Facebook Gaming etc. = TCP – Speedtest.net
Run the test and write down your upload speed which is the speed you need to know for determining your bitrate.
Converting Bytes to Bits & More
Grab your calculator, I did, we have to do a little math in this section. I’m sorry, but it’ll be easy, I promise.
When you run a speed test, you’re going to get your results in Megabytes per second (Mbps). You can now do a direct conversion of Megabytes to Kilobytes.. You’ll want to convert from mbps to kbps because your upload test usually measures in Megabytes and OBS measures bitrate in kbps.
Let’s assume your download speed is 5Mbps. We will want to convert 5 megabytes to kilobytes.
5 * 1000 = 5000
5000 is your bitrate in kbps. However, you never want your bitrate to be your maximum upload capacity. You need to leave some left over for online gaming, music streaming etc. I recommend that your bitrate is never higher than 80% of your upload speed.
.80 * 5000 = 4000
Therefore, if your upload is 5mbps your maximum bitrate can be 4000.
Maximum Bitrate Set by Mixer & Streaming Sites
Keep in mind that it costs streaming sites lot money to run the servers for streaming, as such they will often implement a maximum bitrate.
Mixer – 10000kbps
Twitch – 6000kbps
Youtube Gaming – 9000kbps max recommended, no enforced limit
Bitrate is Not Only for the Streamer but the Viewer too
Whatever bitrate you are uploading your stream at you will need to keep in mind that your viewer will have to download your stream at the same bitrate. The average download speed around the world is ~5mbps.
This is important because you’ll need to keep in mind if someone is watching off their phone in South America with a download speed of 3mbps your stream will lag for them even if your stream uploads to the ingest server perfectly and gets distributed to their phone correctly.
Video Resolution & FPS
Everyone wants to stream 1080p and 60FPS because they want the best video quality. However, for new streamers and sometimes even partners, it’s recommended that you stream in 720p 30FPS or 60FPS especially if your upload speed is 5mbps or less. This relates back to having your stream be viewable by a wider range of viewers across the world with lower download speeds.
Xbox Streaming direct to Mixer
If you stream directly to Mixer from your Xbox, then your bitrate, FPS, resolution are all handled by your Xbox. The bitrate will fluctuate in order to keep your stream live at the cost of quality. When you stream directly from your Xbox, I recommend using an ethernet cable directly to your modem/router to reduce fluctuations.
In conclusion, check your upload speed, do the math, set your resolution and FPS to 720p 30FPS respectively and try it. Ideally, you want at least 3mbps upload speed to have a decent quality stream and never set your bitrate to more than 80% of your upload speed.
I’ll be writing another article about OBS/SLOBS settings in the future, so keep an eye out for it!