Guests were known as "The True Testers of Roblox" by the administrators. When a player hovers the mouse over a guest image when viewing game servers, the name used to appear as "A Friendly Guest". This was changed to read "A Roblox Player", before the Guest feature was removed. As a little easter egg, If a player scrolled on a guest with a "666" number, it will read "An Evil Guest".
If a player joined a game while not logged into an account, they would be labeled as a "Guest".
It was possible to be a guest by either using glitches or using trustworthy unofficial extensions, which allowed one to play as a guest. This was patched in early November 2018.
Guests now get Error code: 524 (Not authorized to join this game.) when attempting to join a game.
On November 4, 2017, Roblox re-added guests by mistake. This change lasted for a day before being reverted.
From 2008 to 2014, guests were able to speak by only using the Safe Chat words. With the removal of Safe Chat in 2014, though, they became completely unable to speak or see messages sent by others, which meant guests would have to create an account to chat in any way. Sometime in 2016, guests were given the ability to see any messages sent by others.
From June 2017 to October 2017, players using the Guest feature were only given 20 trial plays before they had to create an account on Roblox to continue playing; prior to that date, they had been given unlimited trial plays. This was to encourage them to try out the game and eventually, create an account to play on Roblox. A notification would appear for anyone playing as a guest to remind them of the number of trial plays remaining.
Roblox stores a cookie on the user's computer that keeps their ID. Cookie editors (such as EditThisCookie) are able to change a guest's ID number by changing the UserID in "GuestData." Guests have a randomly assigned number from 0 to 9999 whenever they enter a place. Other than users who joined before the removal of spaces in usernames, they are the only users who could have spaces in their username.
When guests played games that save data (like in-game money), they lose their data after exiting.
When guests were first introduced in 2008, they appeared in the classic noob colors of yellow head and arms, blue torso and green-yellow legs.
Later, Guests would be given the same appearance as the "ROBLOX" account, including hats, allowing Guests to technically "try" accessories and have the ROBLOX account's gears.
After that, gender options were added, allowing Guests to appear as "BillyBloxxer" or "BettyBloxxer. They had very similar appearances to the user ROBLOX but had different hats depending on the gender chosen. BillyBloxxer wore the Red Roblox Cap, while BettyBloxxer wore the Pinktastic Hair. The DefaultGuest user originally didn't have an accessory and was all black with a grey torso and a white head.
On July 12, 2016, the appearances of the guests were modified for the first time in a while. The male guest (BillyBloxxer) now wears a Roblox jacket, black jeans, and the True Blue Hair. The female guest (BettyBloxxer) is similar to the male guest except with the Lavender Updo Hair, which looks similar to the Chestnut Bun, except it is a different color. The other guest type (DefaultGuest) looks similar to both the other guest types except is still bald. On September 13, 2016, guests began to wear the Robloxian 2.0 package and the DefaultGuest started wearing the Roblox 'R' Baseball Cap. Sixteen days later, the R15 body was applied to guests. If the game was set to R6 Only, then R6 would have been applied. After Roblox introduced a new logo, the guest's shirt changed to the new Roblox Logo Jacket on January 16, 2017 (six days after the logo began usage).
On July 1, 2017, some guests had grey skin body and each different colored torso due to the avatar update. The torsos were later turned back to normal later that same month.
If playing on mobile, users will be loaded as a genderless guest (DefaultGuest). All guests that joined a game on mobile Roblox versions wear a Roblox jacket and jeans, the 2.0 body, and the Roblox 'R' Baseball Cap due to not being able to choose if they want to be a male or female guest in the mobile versions.
Guests were criticized mostly for being new and clueless players. They were also criticized for being commonly used to exploit in games, and thus being able to evade bans easily.
There have been various petitions on Roblox to remove Guests, but Shedletsky stated that guests were not going to be removed. Contrary to this statement, Nightgaladeld confirmed that Guests would be removed..
On October 3, 2017, Guests were officially removed from Roblox, though you could still get in the game as a guest after that for many different reasons until November 24, 2018 when they were fully removed, as when you try to get in a game, it shows an error code. Nightgaladeld stated that the reason was to increase the number of users in Roblox. Despite the removal, guest toys are still being sold in stores. Now, unregistered users can still access the website, but cannot play games, change an avatar, leave comments, or create things. Some players liked this idea; however, most players were angry at Roblox and started protesting in places like the Roblox forum to bring them back.
There have been numerous sightings of guests in games even after the removal, mostly from people using third-party tools to join games as guests or using mobile.