Overview
The Mystery Market username checker looks up Roblox’s public user API. You get a clear taken / available result without installing anything or signing in.
Use it before you rebrand, create an alt, or buy a limited — confirming the exact spelling of a delivery username avoids failed trades.
Related: Open username checker · Username & display name ideas · All free tools
Steps
- 1
Open the username checker
Go to Tools → Username checker (or open /tools/username-checker directly). The page works on desktop and mobile browsers.
- 2
Enter the username
Type the Roblox username you want to check. Usernames are 3–20 characters and use letters, numbers, and underscores — no spaces.
- 3
Read the result
If the name is taken, we show the profile’s username, display name, user ID, and headshot when available. If no public account matches, we mark it available. Reserved or moderated strings can still be blocked by Roblox at signup even when no profile exists.
- 4
Use the ID for delivery
When buying on Mystery Market, double-check the Roblox username you enter at checkout matches the profile you intend. A one-letter typo sends the trade to the wrong person.
Tips
- Display names are not unique — always verify the actual @username.
- Availability does not reserve the name; someone else can claim it before you finish signup.
- Rate limits keep the free tool fair; wait a moment if you hit a temporary throttle.
FAQ
- Is the username checker free?
- Yes. It is free on Mystery Market with no account required for basic lookups.
- Does available mean I can register it?
- Usually for unused valid names. Roblox may still reject reserved, offensive, or previously locked strings.
- Do you store the names I search?
- Lookups are processed to return a result. See our Privacy Policy for how we handle technical logs.
Shop on Mystery Market
Full catalog →Pay with card or Robux — no Discord account required.