The math that matters
Add up the video and audio bitrate of each local output. Then leave a margin for Wi-Fi, other people on the network and swings from your provider. YouTube recommends aiming for 1.5 to 2 times the combined bitrate when simulstreaming.
Corneta's Quality screen already says fits your upload with room to spare at 20% headroom. On Wi-Fi or a shared network, aim for the 1.5× to 2× range.
If Twitch uses 6 Mb/s and YouTube uses 4 Mb/s, the total is 10 Mb/s. The stable upload to aim for sits between 15 and 20 Mb/s. That is not a promise from your provider: it helps you decide whether this setup is worth testing.
Do the math
How much will your stream need?
Use the video + audio bitrate of each local output.This range uses the 1.5× to 2× margin YouTube recommends for multistreaming. Test with real audio, camera and motion before going live.
What goes into the total
Every destination that leaves your PC directly counts. If three platforms get 6 Mb/s each, you are not using 6 Mb/s: you are trying to sustain close to 18 Mb/s, plus audio, protocol overhead and fluctuations.
A cloud relay changes the local math. Your PC sends one output to the relay, and the relay copies it out on its side. You use less upload at home, but you now depend on that service and the limits of its plan.
Your plan's Mbps is not stable Mbps
The number on your plan is a ceiling, not a guarantee of stability every second. Run the test on the same network, at the same time of day and with the cable or Wi-Fi you use when you stream.
OBS explains that dropped frames show up when the connection to the server can't keep up with the bitrate you set. A quick test can show a high number and still hide packet loss, jitter or short drops.
Test with your real stream
- Close backups, sync and downloads on other devices.
- Open your game, camera, microphone, alerts and your heaviest scene.
- On the Live screen, use Upload bandwidth → Measure now while you are not streaming.
- Do an unlisted or test stream with every destination.
- Watch bitrate and dropped frames for a few minutes, especially in scenes with motion.
If the math doesn't add up
Lower the bitrate of the least demanding destination first. Then look at FPS and resolution. Switching from All out to Smart takes load off your PC: Twitch, YouTube and Kick get a copy of the OBS signal, and only destinations that need vertical video are transcoded. Your upload changes too, because each copy goes up at the OBS bitrate. Check the number on the mode's card before you decide.
If your connection can only hold one good output, use a cloud relay. Fighting an upload that is already at its limit usually ends in dropped frames at the worst moment.
See the full comparison in local or cloud multistream.