At LockerGnome.net, Lestat611 writes:
How much bandwidth would I need to live stream 720p/1080p video and audio?
Bandwidth depends on the software you’re using to live stream. Different software providers use different codecs and those codecs can, and do, change the quality of the stream versus the bandwidth that you have available to you. The general consensus of the streaming services that I’ve looked at is that a 700 Kbps or higher upstream will give you a quality live stream. They may not say 720p, but I do know that it would be possible with the right codecs.
There have been many arguments in streaming forums about how much bandwidth is required to have produce a great quality live stream. There are some who say that anything over 2 Mbps is what’s required for 720p live streaming. It has been proven that it is possible to produce a live stream of a high enough quality to be watched at 1 Mbps and under for a stream at 720p. The stream’s quality won’t be the best, but it all depends on why you want to stream live.
If you are live streaming for the fun of live streaming, then anywhere between the 700 Kbps and 1 Mbps would probably suit you. If you are live streaming for a living, like a YouTuber giving extra value to his/her audience, then 1 Mbps to 2 Mbps would probably be the better option for you.
I will also point out that this is your upstream and not your downstream. Most people will say that they have a certain Internet speed when that’s only half the story. Upstream is the second number that places like speedtest.net test give you. If you’re looking to build a separate live stream machine on the cheap, we also have an article for that. I hope that’s helped you.