How do you find what website pages are creating 404s?

Using Google Analytics to discover which website pages are creating 404s.

This came from HubSpot community-  it works really well!

We utilize Google Analytics and run a Page Report with a Secondary Dimension of Page Title...and then filter Page Title by "(not set)".... Hubspot leaves the Page Title blank on 404 pages and this seems to work pretty well for us

Here is an example of the report with pages we want to fix