Question 1

How do I find someone's User ID on Roblox?

Accepted Answer

Type the username in the Lookup tab. The ID shows up large, with a copy button. On the website the same number is in the profile address: roblox.com/users/156/profile is the account with ID 156 (builderman). You can also paste that whole link here and the tool extracts the ID.

Question 2

Does the User ID change when someone changes their username?

Accepted Answer

No. The ID is the permanent identifier of the account and only the name changes. That is why you should store the ID in DataStores, allowlists and group payouts. If you stored only the name, it can end up pointing to someone else when another person registers the old name.

Question 3

What is the difference between a username and a display name?

Accepted Answer

The username is unique, has 3 to 20 characters (letters, numbers and at most one underscore, never at the start or end) and is not case sensitive. The display name is what shows up in games and can repeat across accounts. The lookup shows both, and the ID settles any doubt about who is who.

Question 4

How do I know if a username is available?

Accepted Answer

Use the Username checker tab. It applies the format rules instantly and, if the format is right, asks Roblox for the same check used at sign-up. Code 0 means available, 1 in use, 2 rejected by moderation, 3 invalid length, 4 underscore at the start or end, 5 too many underscores, 6 spaces, 7 invalid characters. Available does not reserve the name, and the real sign-up may still apply other filters.

Question 5

Why does a name show as in use when the account is gone in the app?

Accepted Answer

The lookup includes banned or terminated accounts, which the card marks with a notice. The profile of such an account may not open in the app or on the website even though the name is still registered. If a name shows as in use here and you cannot find the profile, search by ID instead.

Question 6

How do I see an account's past usernames?

Accepted Answer

Run the lookup and click Show past usernames. Roblox allows only 1 request per minute for that data from our server's IP, shared by all visitors, so sometimes you will see a notice to try again in a few seconds. When it works, the result is cached for 1 hour. Accounts that never changed their name show an empty list.

Question 7

How many usernames or IDs can I convert at once?

Accepted Answer

Up to 50 at a time, in a single call to Roblox. Paste one per line or separated by comma, space or semicolon. Duplicates are removed (ignoring case), invalid names are listed separately, and names not found appear in the table. You can copy only the IDs, only the names, or export CSV and TXT.

Question 8

How do I convert a username to an ID inside a Luau script?

Accepted Answer

Use Players:GetUserIdFromNameAsync("name") for name to ID and Players:GetNameFromUserIdAsync(id) for ID to name. Both make a web call, can be slow and raise an error if the account does not exist or the service fails, so wrap them in pcall. Every profile looked up here comes with ready snippets, including the pcall version.

Question 9

Why are friends, followers or following sometimes blank?

Accepted Answer

Roblox rate-limits each count per minute for the server IP: about 100 friend-count requests, 10 following-count and only 1 follower-count per minute, values measured in October 2026 that Roblox may change. When the quota runs out, the field shows a dash instead of blocking the profile, and counts we did get stay cached for 10 minutes.

Question 10

Does the tool store data or access private information?

Accepted Answer

It accesses nothing private: it asks for no login, password or cookie, and reads only data Roblox already publishes (name, description, creation date, avatar and public counts). The names and IDs you type go to our server only to query the Roblox API and are not stored; only the public result stays cached for a few minutes. The tool is not affiliated with Roblox.

Code	Meaning
0	Available to register Roblox accepted this name in the sign-up check.
1	Already in use An account with this name exists. Usernames are unique and not case sensitive.
2	Rejected by moderation Roblox's content filter blocked this name as inappropriate for the platform.
3	Invalid length The name must be 3 to 20 characters long.
4	Underscore at the start or end The name cannot start or end with _.
5	Too many underscores The name can have at most one _.
6	Contains spaces Spaces are not allowed. Use an underscore instead.
7	Characters not allowed Only letters A to Z (no accents), digits 0 to 9 and one underscore are valid.
10	Looks like personal information Roblox's documentation describes this code as a name that contains personal data, such as a phone number or email.
12	Reserved name Roblox's documentation describes this code as a name reserved by the platform.

Code	Meaning
0	Available to register Roblox accepted this name in the sign-up check.
1	Already in use An account with this name exists. Usernames are unique and not case sensitive.
2	Rejected by moderation Roblox's content filter blocked this name as inappropriate for the platform.
3	Invalid length The name must be 3 to 20 characters long.
4	Underscore at the start or end The name cannot start or end with _.
5	Too many underscores The name can have at most one _.
6	Contains spaces Spaces are not allowed. Use an underscore instead.
7	Characters not allowed Only letters A to Z (no accents), digits 0 to 9 and one underscore are valid.
10	Looks like personal information Roblox's documentation describes this code as a name that contains personal data, such as a phone number or email.
12	Reserved name Roblox's documentation describes this code as a name reserved by the platform.

Roblox User Lookup (User ID and Username)