What the relay removes before Meta sees an event

Every event goes through the same clean-up on the server, before it is sent to Meta. Some steps always run, others follow the website's privacy settings.

Page addresses#

The referring site is never sent to Meta.

Event names#

Your event name is replaced with the Meta event it is mapped to. A name with no mapping is sent as a meaningless code like evt_a1b2c3d4, so an unexpected name like ivf_enquiry does not reach Meta as text.

Event details#

Only value, currency, content_ids, num_items, content_name, content_type and content_category are kept. Everything else your site sends in the event's details is dropped.

• content_ids are replaced with short codes like item_1f3a9c2b.
• content_name, content_type and content_category have blocked terms replaced, like page addresses.

Customer details#

Hashing is what Meta asks for: it can match a hash to its own users, but the relay never sends the readable value. The relay does not store these hashes either.

Visitor and browser#

• IP address: sent to Meta only when Send visitor IP and browser to Meta is on. The relay never stores it; it keeps a keyed hash to count unique visitors.
• Browser: the user agent string is sent, so Meta can tell a phone from a desktop.
• Meta's own cookies: when the visitor has Meta's _fbp or _fbc cookie, or arrived from a Meta ad with fbclid in the address, those values are passed on, as Meta's own pixel would.

What this does not cover#

The relay cleans what it receives. It cannot see or change anything else on your site, such as other tracking scripts, chat widgets or a Meta Pixel installed separately. Check those too.