The Safe Browsing APIs (v4) let your client applications check URLs against Google's constantly updated lists of unsafe web resources. To determine if a URL is on any of the Safe Browsing lists, clients can send URLs to the Google Safe Browsing server to check their status or download encrypted versions of the Safe Browsing lists for local, client-side checks of URLs.
What are the Safe Browsing APIs?
The Safe Browsing APIs (v4) let your client applications check URLs against Google's constantly updated lists of unsafe web resources. Examples of unsafe web resources are social engineering sites (phishing and deceptive sites) and sites that host malware or unwanted software. Any URL found on a Safe Browsing list is considered unsafe.
To determine if a URL is on any of the Safe Browsing lists, clients can use either the Lookup API (v4) or the Update API (v4).