What this checker does, and doesn't
It checks your username's format against each platform's published rules: length, allowed characters and where periods can go. That all runs in your browser, so nothing you type is sent anywhere.
It doesn't look up whether a name is taken. Platforms don't offer a public way to do that, and tools that claim to are often guessing. Instead, each row links to the profile address, so you can see for yourself in a second.
How to tell if a username is taken
Open the profile link. What you see tells you most of what you need:
- A profile loads: the name is taken.
- "Sorry, this page isn't available" or "This account doesn't exist": the name is probably free.
- The page asks you to log in: log in and try again, since some platforms hide profiles from people who aren't signed in.
Common reasons a handle is rejected
Most format problems come down to a handful of things. Check these first if a platform turns your name down:
- Periods on X or Twitch, which only allow letters, numbers and underscores.
- Length: X stops at 15 characters and TikTok at 24, while Instagram allows 30.
- A period at the end, which Instagram, Threads and TikTok all refuse.
- Spaces, accents or emoji, which none of the major platforms allow in a username (YouTube handles do accept letters from many alphabets).
- Words a platform keeps for itself, like X's ban on usernames containing "twitter" or "admin".
When a name looks free but isn't
Platforms hold some names back: ones that belong to suspended or deactivated accounts, names someone changed away from recently, and reserved or trademarked words. The real test is the sign-up or edit-profile screen, which tells you straight away if a name can't be used.
If your first choice is held, a small change usually works: an underscore, a word like studio or hq, or your city.
Getting one handle everywhere
Matching handles make you easier to find and to tag, and look tidy on a media kit. X has the strictest common rules: 15 characters at most, using only letters, numbers and underscores. A name that passes those works on nearly every other platform too.
The same goes for your link-in-bio address. Hiyaly handles use lowercase letters, numbers, hyphens and underscores, so a name that works on X usually works there too.
Frequently asked questions
Can this tool tell me if a username is taken?
No. It checks the format against each platform's rules. To see if a name is free, use the Open profile links: if the profile doesn't exist, the name is probably available.
Why does my username work on Instagram but not on X?
X only allows letters, numbers and underscores, up to 15 characters. Periods, and longer names that Instagram accepts, won't work there.
Are usernames case-sensitive?
No. On the major platforms, MayaChen and mayachen are the same username. Some let you show capitals in your display name, which can make a long handle easier to read.
What's the maximum username length on each platform?
Instagram and Threads allow 30 characters, TikTok 24, X 15, Twitch 25 and YouTube handles 30.
Why is a username unavailable when no profile shows up?
The platform may be holding it. It could belong to a suspended or deactivated account, or have been given up recently. Try a small variation instead.