Universal Analytics offers an IP-address masking feature that truncates user IP addresses to enhance privacy and comply with data protection regulations. The process occurs in memory before any data is stored, ensuring full IP addresses are never recorded. Website owners can implement this feature using the anonymize_ip configuration in the gtag.js library.

• IP masking zeroes out the last octet of IPv4 addresses and the last 80 bits of IPv6 addresses almost immediately after Google Analytics receives the data.
• Truncation happens in memory before any storage occurs, so the full IP address is never written to disk.
• Enabling the feature only requires setting the anonymize_ip parameter (aip=1) via gtag.js.
• Even with masking, enough geographic information survives in the truncated address to still support location-based reporting.