What is the Ideal Latency for Video Streaming?
To stream smooth video, you need an internet connection with high throughput speeds and low latency. What is the ideal latency, or ping time, is the time it takes for your network to connect to the host and begin transferring data over the internet? In many cases, the latency of your connection affects video streaming more than the speed of your connection.
Latency varies from less than 10 milliseconds on some cable internet connections to more than 1 second on some satellite internet connections. A latency of greater than 100 milliseconds can cause severe lags in your connection, which can slow down video streaming and lead to frequent buffering on platforms like YouTube, Netflix, and Hulu.
To discover the latency of your internet connection, run an internet speed test. If your video is lagging because your internet connection has high latency (i.e. a latency of greater than 100 milliseconds), you can speed up your video stream by changing your playback settings or by changing your internet connection.
To Prevent Lagging, Lower your Playback Quality
If your internet connection has high latency and slow throughput speeds, then the read-ahead buffer will be short for high-definition (HD) videos with larger data packets than standard-definition (SD) videos. To increase the read-ahead buffer on these types of internet connections, decrease the quality of your video in playback settings.
On YouTube, decrease the quality of a video by:
- Opening a video
- Clicking the gear icon (“Settings”) in the lower right-hand corner of the video
- Choosing “Quality” from the settings menu
- Selecting a lower playback quality
On Netflix, decrease the quality of a video by:
- Navigating to the “Your Account” page
- Selecting “Playback settings” under “Your Profile”
- Choosing a lower data use setting
On Hulu, decrease the quality of a video by:
- Opening a video
- Clicking the gear icon in the lower left-hand corner of the video
- Selecting a lower video quality
If you have an internet connection with high latency, but fast throughput speeds, then playback quality will have less of an effect on the read-ahead buffer. A fast connection will be able to process large data packets from HD videos quickly, even if the network takes a long time to connect to the host each time it sends a packet.
If you’re live streaming on an internet connection with high latency, the quality of your video will suffer since live streaming platforms like YouTube automatically balance latency and playback quality. If your connection is fast enough, you can manually adjust the latency of your YouTube live streams to improve the playback quality of your livestreams.
Ideal Latency by Type of Internet Connection
Do you need to change the type of internet connection you use to stream video? Average latency varies significantly depending on the type of internet connection you’re using:
| Internet connection | Average latency |
|---|---|
| Cable internet | ~20 milliseconds |
| DSL internet | ~40 milliseconds |
| Mobile broadband (4G LTE) | ~70 milliseconds |
| Satellite internet | >500 milliseconds |
Streaming Video on a Wireless Internet Connection
Unfortunately, wireless internet connections (like satellite and mobile broadband) have a higher base latency than wired connections (like cable and DSL). If you need to use a wireless connection and are looking to 
decrease your latency and find the ideal latency, mobile broadband is your best option.
While satellite often has a latency of more than 1 second, most mobile broadband connections have a latency of less than 100 milliseconds. In 2017, all major 4G LTE networks in the United States had an average latency of less than 70 milliseconds. AT&T, which had the lowest average latency, connected to the host in just 58.29 seconds.
While 3G still has a lower latency than satellite, it isn’t the ideal latency for video streaming. In 2017, the average 3G connection had a latency of less than 200 milliseconds. Even T-Mobile connections, which had an impressive average latency of 109.41 milliseconds, would cause severe lags in video streaming.
