Security: Understand security issues

Use the Security Panel in Chrome DevTools to make sure HTTPS is properly implemented on a page. See Why HTTPS Matters to learn why every website should be protected with HTTPS, even sites that don't handle sensitive user data.

Open the Security panel

The Security panel is the main place in DevTools for inspecting the security of a page.

  1. Open DevTools.
  2. Click the Security tab to open the Security panel.

    The Security panel

    Figure 1. The Security panel

Common problems

Non-secure main origins

When the main origin of a page is not secure, the Security Overview says This page is not secure.

A non-secure page

Figure 2. A non-secure page

This problem occurs when the URL that you visited was requested over HTTP. To make it secure you need to request it over HTTPS. For example, if you look at the URL in your address bar, it probably looks similar to To make it secure the URL should be

If you've already got HTTPS set up on your server, all you need to do to fix this problem is configure your server to redirect all HTTP requests to HTTPS.

If you don't have HTTPS set up on your server, Let's Encrypt provides a free and relatively-easy way to start the process. Or, you might consider hosting your site on a CDN. Most major CDNs host sites on HTTPS by default now.

Tip The Redirect HTTP Traffic To HTTPS audit in Lighthouse can help automate the process of making sure that all HTTP requests are redirected to HTTPS.

Mixed content

Mixed content means that the main origin of a page is secure, but the page requested resources from non-secure origins. Mixed content pages are only partially protected because the HTTP content is accessible to sniffers and vulnerable to man-in-the-middle attacks.

Mixed content

Figure 3. Mixed content

In Figure 3 above, clicking View 1 request in Network panel opens the Network panel and applies the mixed-content:displayed filter so that the Network Log only shows non-secure resources.

Mixed resources in the Network Log

Figure 4. Mixed resources in the Network Log

View details

View main origin certificate

From the Security Overview click View certificate to quickly inspect the main origin's certificate.

A main origin certificate

Figure 5. A main origin certificate

View origin details

Click one of the entries in the left-hand nav to view the origin's details. From the details page you can view connection and certificate information. Certificate transparency information is also shown when available.

Main origin details

Figure 6. Main origin details