Effective connection type

Effective connection type (ECT) refers to the measured network performance, returning a cellular connection type, like 3G, even if the actual connection is tethered broadband or Wi-Fi, based on the time between the browser requesting a page and effective type of the connection.

The values of 'slow-2g', '2g', '3g', and '4g' are determined using observed round-trip times and downlink values.

ECT Minimum RTT Maximum downlink Explanation
slow-2g 2000ms 50 Kbps The network is suited for small transfers only such as text-only pages.
2g 1400ms 70 Kbps The network is suited for transfers of small images.
3g 270ms 700 Kbps The network is suited for transfers of large assets such as high resolution images, audio, and SD video.
4g 0ms The network is suited for HD video, real-time video, etc.

effectiveType is a property of the Network Information API, exposed to JavaScript via the navigator.connection object. To see your effective connection type, open the console of the developer tools of a supporting browser and enter the following:


See also