Opera 40 is a web browser developed by Opera Software ASA, available for download in full install version for Windows platforms from legacy sources. This version of Opera was officially released on 2016-09-20 for public access and a brief summary of important updates and change log pertaining to this edition can be read below.

Opera 40 has been built on Chromium 53 rendering engine and has and most important update of built-in Free VPN service other than improved functionalities like automatic battery saving, Chromecast support and video pop out improvements.

Opera becomes the first browser to provide built-in VPN service and users can choose whether it can be in-effect only during private or normal browsing sessions. In this edition Battery saving mode would be automatically activated when the laptop main power is unplugged.

Though there are complexities in using it, now Opera supports Chromecast and can play YouTube videos only. Video Pop Out has been improved in this version and videos created in more sites and apps can be pop-out now.