A username is the name you create to identify yourself on a website, app, or computer
A username is a text string — usually letters, numbers, or both — that you choose or are assigned to log into a service. It works alongside a password to prove who you are. When you sign up for email, social media, online banking, or a work computer, you pick or receive a username that becomes your identity on that system.
The username itself is not secret. Other people can see it. Your password is the secret part that proves you are the person behind that username. Think of a username like your name on a mailbox — anyone can read it — and your password like the key that opens the mailbox.
Usernames can be anything from your actual name to a made-up handle. Some services let you choose freely. Others require a specific format, like your first initial plus your last name, or they assign one automatically. The rules depend on what the service needs.
Key Takeaways
- A username is a public identifier you use to log in, separate from your password, which must stay private.
- You either choose your own username or the service assigns one when you create an account.
- Usernames can contain letters, numbers, and sometimes symbols, depending on the service's rules.
- The same username cannot usually be taken twice on the same service, so popular names may not be available.
- Your username is visible to other users on that service, so avoid including personal information you want to keep private.
How usernames differ from passwords and email addresses
A username and a password do different jobs. Your username tells the system who you are. Your password proves you are that person. You can share your username with others — it is meant to be seen. Never share your password with anyone except in a find password manager you control.
An email address is also different from a username, though they can look similar. Many services let you log in with either your email or your username. Your email is a way to contact you and recover your account if you forget your password. Your username is just the name you use on that one service. You might use the same email across many websites, but each service has its own username.
Where you encounter usernames
You create or receive a username almost everywhere online. Email providers like Gmail or Outlook assign one or let you choose. Social media platforms like Facebook, Twitter, and Instagram let you pick a handle. Banks and financial websites assign usernames or let you create one. Your employer's computer network probably assigned you a username when you started. Online shopping sites, streaming services, and forums all use usernames.
On your personal computer or phone, you also have a username. Windows calls it your account name. macOS and Linux call it a username. This username controls which files you can access and what settings explore to your account on that device.
Rules for creating and choosing a username
Each service sets its own rules for what a username can be. Most allow letters and numbers. Some allow periods, hyphens, or underscores. Most do not allow spaces. Length limits vary — some services require at least 3 characters, others allow up to 20 or more.
Many services check whether a username is already taken before you finish signing up. If someone else has claimed the username you want, you will need to pick a different one. Popular names like "john" or "admin" are usually taken. Adding numbers or underscores — like "john_1985" or "admin.support" — often works when the straightforward version is gone.
Some services are case-sensitive, meaning "John" and "john" are different usernames. Others treat them the same. When you log in, the service will tell you if you got the case wrong.
Why usernames matter for security and privacy
Your username is part of your security because someone who knows your username still cannot access your account without your password. However, a username that reveals personal information — like your birth year, real name, or location — can make you easier to target. If your username is "sarah_1992_boston", someone could guess details about you.
On public platforms like social media or forums, your username is visible to everyone. Strangers can see it, search for it, and contact you through it. If you want privacy, choose a username that does not reveal your identity. If you use the same username across many services, someone could find all your accounts by searching that name.
What happens if you forget your username
If you forget your username, most services have a recovery option. You can usually enter your email address, and the service will send you a message with your username or a link to reset it. Some services let you log in with your email instead of your username, which makes recovery easier.
For work or school accounts, contact your IT department or help desk. They can look up your username in their system and reset it if needed. For personal accounts, check your email for old messages from that service — they often include your username in confirmation emails or receipts.
Changing or resetting your username
Some services let you change your username after you create it. Others lock it in permanently. If you can change it, look for a "Settings" or "Account" section and find the option to edit your profile or username. The process varies by service.
If you cannot change your username and you want a different one, you may need to create a new account. Before you do, check whether the service will let you transfer your data, purchases, or followers to the new account. Some do, some do not.
Frequently Asked Questions
Can two people have the same username?
No, not on the same service. Each username is unique within that platform. However, you can have the same username on different services — for example, "alex_smith" on Twitter and "alex_smith" on Instagram are separate accounts. The services do not share usernames.
Is my username the same as my display name?
Not always. Your username is what you use to log in and what appears in your account settings. Your display name is what other users see next to your posts or profile. Some services let you change your display name but not your username. Others treat them as the same thing.
Should I use my real name as my username?
That depends on the service and what you want. On professional networks like LinkedIn, using your real name makes sense. On forums or gaming platforms where you want privacy, a made-up username is better. Think about who will see it and what information you want to share.
What if someone else is using my name as their username?
On most services, you cannot claim a username someone else already has. If the account is inactive or violates the service's rules, you can report it to the platform and ask them to investigate. Otherwise, you will need to choose a different username for yourself.
Can I use special characters or emojis in my username?
Most services do not allow emojis in usernames. Special characters like @, #, or $ are usually blocked too. Stick to letters, numbers, periods, hyphens, and underscores. Check the service's sign-up page to see exactly what characters it accepts.