IP users, guest users, or unregistered users are users who edit Wikipedia without registering for an account. The term "IP user" comes from the fact that when such a user edits, Wikipedia annotates the edit with the IP address of the computer from which the edit was made where, if the user were logged in, it would show the username of the editor who made it. These substitutes for usernames may have the following general IPv4 or IPv6 forms:

x.x.x.x where x is a number bigger than 0 and smaller than 255

y:y:y:y:y:y:y:y where y is a number between 0 and 65535, written in hexadecimal

The IP user edits are estimated to constitute one-half (54% in 2013) of the general username activity levels. So, among the total daily edits, then about one-third are posted by IP users, while 2/3 (~67%) are logged to specific usernames each time.

While registered editors only occasionally possess one or two legitimate alternate usernames, IP users frequently contribute from different IP addresses because Internet service providers (ISPs) usually assign IP addresses dynamically; meaning that the same actual person may return to Wikipedia with a different IP address that was re-assigned by the ISP. This often makes it difficult to tell whether an IP user is a total newcomer or a returning editor.

• IPv4 address exhaustion
• IPv6

Help desk

• Advice for parents – A brief introduction to Wikipedia for parents and legal guardians.
• Contributing to Wikipedia – A page that explains how and where you can help Wikipedia.
• Deleting and merging accounts – A page that explains why it is not possible to delete user accounts and the alternatives available.
• Personal security practices – A page that explains how caution should be used when posting personally identifiable information online.
• Privacy, confidentiality and discretion – A page that explains how your rights to privacy may not extend as far as you believe.
• Request an account – A page that explains how any editor may request an account be created for them.
• Why create an account? – A part of the FAQ that talks about the reasons to edit as a registered user.
• Why not create an account? – A page that talks about the reasons to edit as an IP.
• Wikipedia is in the real world – A page that explains how activity here on Wikipedia has consequences in the real world.