Stream latency is the delay between your camera capturing an event and the event being displayed to viewers. When setting up your live stream, think about how the level of latency may affect your viewers.
- Lower latency: If you live chat with viewers, a lower latency is best to reply to viewer comments and questions.
- Note: Lower latency, your viewers may experience more playback buffering.
- Higher latency: If you don't interact with your audience, higher latency is not a problem.
Trade-off between latency and quality
The lower the latency, the less read-ahead buffer the video player will have. The amount of read-ahead buffer is important because it's the main source of stream latency. With a lower latency, viewers are more likely to feel the issues between the encoder and the player.
Network congestion and other factors may also cause live streaming issues, which can delay your stream. Delays can happen even when you have a great network that can sustain your average streaming bitrate.
Generally, your viewers' player can handle these changes in internet speed by keeping some extra live stream data. This function is called Buffer Health in Stats for Nerds.
Manage your latency setting
In Live Control Room:
- Go to YouTube Studio.
- From the top right, click Create
Go live
.
- Enter your live stream details.
- On the right menu, click Stream or Manage.
- From the stream dashboard, click Stream Settings.
- Under "Stream latency," select your latency.
Webcam and mobile streaming are always set up for interactivity. You cannot set a live stream latency for them.
Latency options for live stream
Normal latency
Best for: non-interactive live streams
Choose "Normal latency" if you don't plan to interact with your audience in the live stream. This option is the highest quality setting for viewers since it has the lowest amount of viewer buffering.
All resolutions and live features are supported at Normal latency.
Low latency
Best for: limited audience interaction
Choose this option if you plan to have limited interaction with your audience and don't need to wait for responses, such as with polls. Most viewers of a low-latency stream will experience latency less than 10 seconds. This setting is a good balance between the other two options.
This setting does not support 4K resolution.
Ultra-low latency
Best for: highly interactive live streams with real-time engagement
Choose this option if you want to converse with your audience. Most viewers of an ultra-low latency stream will experience latency less than 5 seconds. It may increase the chances that your viewers get buffering.
This setting does not support 4K resolution.
Note: live ingestion issues on your network will affect viewers more in this setting. Make sure your network connection can sustain streaming at the bitrate of your choice. For best results, use AV1 or HEVC for the best quality and stability at any bitrate and follow YouTube Live’s encoder recommendations here.