What Is PII?

Personally Identifiable Information (PII) is any data that can identify a specific individual, including names, email addresses, phone numbers, physical addresses, or payment details. Under both GDPR and CCPA, PII remains legally classified as personal data even when it's hashed or partially obscured before transmission.

The word ‘identifiable’ does a lot of work here, and it’s where a lot of confusion happens. Teams often assume Hashing an email address before sending it to a tag makes it anonymous. It doesn’t. Regulators treat hashed PII as still personal data, because it can, in principle, be matched back to an individual, which is why Payload Inspection of tags like the Meta Pixel has to check for hashed fields, not just plain-text ones.