This cookie name is being set on 64,737 websites and 322 distinct domains and we have seen it bein used in the following objects:

64,737 HTTP cookies

Cookie origin and purpose

YouTube cookie (confidence 0.75) » Reference...

Cookie classification

unknown (confidence 1)

Sample values

Sample value:

f1=50000000

Length: 11 bytes (88 bits)
Information entropy: 1.67 bits (average bits per symbol)
Information content: 18.40 bits

Sample value:

f1=50000000&f5=30

This might be a Base64-encoded cookie. Decoded value:

b'\x7f\x9d\xf4'

Length: 3 bytes (24 bits)
Information entropy: 1.58 bits (average bits per symbol)
Information content: 4.75 bits

Sample value:

f5=30

This might be a Base64-encoded cookie. Decoded value:

b'\x7f\x9d\xf4'

Length: 3 bytes (24 bits)
Information entropy: 1.58 bits (average bits per symbol)
Information content: 4.75 bits

Domains targeted by `PREF` cookie

This list includes both third-party domains set by tracking and adversing companies, as well as the first-party domains of the websites that use this cookie name.

Web Cookies Scanner

Cookie: `PREF`

Cookie origin and purpose

Cookie classification

Sample values

Domains targeted by `PREF` cookie

Websites setting `PREF` cookie

Web Cookies Scanner

Cookie: PREF

Cookie origin and purpose

Cookie classification

Sample values

Domains targeted by PREF cookie

Websites setting PREF cookie

Cookie: `PREF`

Domains targeted by `PREF` cookie

Websites setting `PREF` cookie