Chrome Extension which tags items in your Pocket with tags showing how much time you will spend reading given article
https://chrome.google.com/webstore/detail/timetoread/pnoopjphmiljaepnghokldgckdkmmgea
If you are interested in more "complicated" extension (with WebWorker), or with more complicated way of working with tags go to https://github.com/przemelek/PocketTags (or https://chrome.google.com/webstore/detail/pockettags/pajmfleghibikehgnindbajeiffijlgd in Chrome Web Store)