What is Chrome 'Site Isolation' and how does it keep me safe?

The web is a scary place. There are scams, malicious links and other vulnerabilities hiding everywhere. Most users don't see this because of protections built-in to their web browser or email client, and with Chrome 63, Google has brought another key feature to keeping users safe: site isolation.

What is site isolation?

The Chrome browser is known for using a lot of system resources, but with good reason: each tab in the browser is dedicated a single process. This uses more power, but if a website causes one tab to crash, the other tabs continue working without issue and without crashing the entire web browser.

When one tab — for this example, an email client — has an action that opens a new tab — clicking on a link inside an email — both of those tabs share a single process. Another example is if you have one tab for the Android Central home page and another tab for the (awesome) Android Central forums — because these share the same domain, they are also been sharing one single process.

That changes with site isolation in Chrome 63. Each tab will get its own process, no matter what. This does have an impact on system memory: the Chrome browser will use 10%-20% more RAM. Having said that, I've used site isolation on Windows machines with 4GB of RAM and didn't notice any performance impact.

How to enable site isolation

Unfortunately, site isolation is not (yet) enabled by default, but can be easily turned on inside Chrome on Windows, macOS, Linux, Android and Chrome OS. Here's how to enable it on your computer.

  1. Type chrome://flags into the Chrome address bar.
  2. Press Ctrl + F on your keyboard to open the search window.
  3. Search for "Site Isolation." You should see the option listed as "Strict Site Isolation."
  4. Click Enable. The browser will restart, and that's it!

IT administrators can enable Site Isolation for their organization by enabling the policy within the Google Administrative Console.

Should you use site isolation?

Yes. The only (potential) downside is a performance tax, but the protections that come with site isolation are well worth it. It's another layer in the security ogre that will keep you safe in the online world.

Have you started using site isolation? Let us know down below!

Tom Westrick