[joshuahedlund]

> 79% of your readers spent longer than 2+ seconds looking at your email

I understand how opened emails can be tracked without javascript, via server hits to img files, but what magic allows you to track how long it was opened?

[mnutt]

Use the tracking pixel and hold the connection open. When the user goes to the next email, the connection will close and you'll have the length of time they viewed it.

[Aardwolf]

Indeed, the 2 seconds it takes to find the "Unsubscribe" link at the bottom.