What is an email address?
An email address is where your email gets delivered, the way a street address is where your letters get delivered. It always has three parts: a name, the @ sign, and a domain, like jordan.lee@gmail.com.
An email address is a unique name for a mailbox on the internet, written as name@domain. The part before the @ (the username or local part) identifies the person or mailbox. The part after the @ (the domain) is the email service or company that holds the mailbox, such as gmail.com or yourcompany.com. Example: jordan.lee@gmail.com.
See also: New to email? Start with what email is and how it works.
Electronic mail: the definition
Email is short for electronic mail. Merriam-Webster defines it as "a means or system for transmitting messages electronically (as between computers on a network)," and also as the messages themselves. The dictionary dates the word to 1979.
In plain English: email lets you send a written message, with files attached if you like, from one address to another over the internet. It usually arrives within seconds, and it waits in the other person's inbox until they read it. If you're curious how it started, see the history of email.
Wondering whether to write "email" or "e-mail"? Both are in the dictionary, but most style guides now use email.
The three parts of an email address
Take the address jordan.lee@baysidedental.com:
| Part | In the example | What it is |
|---|---|---|
| Username (local part) | jordan.lee | The name of the mailbox. It's unique at that domain: there's only one jordan.lee at baysidedental.com. |
| @ ("at") | @ | Separates the two halves. Read aloud as "at." |
| Domain | baysidedental.com | Where the mailbox lives: an email provider like gmail.com, or a company or personal domain. |
The email standard (RFC 5322) calls this an "addr-spec": a locally interpreted string, the @ sign, and an internet domain. The domain part works like a city and the username like a street address. Mail servers first find the domain, then hand the message to the right mailbox.
Out loud, you'd say jordan.lee@baysidedental.com as "jordan dot lee at bayside dental dot com."
How an email finds the right address
You don't need to know this to use email, but it explains a lot of error messages:
- You press Send. Your email app hands the message to your provider's mail server.
- That server looks at the domain after the @ and asks the internet's address book (DNS) which server accepts mail for it. This is called an MX record.
- It passes the message to that server.
- The receiving server looks at the username before the @ and drops the message into that mailbox.
If the domain doesn't exist, or the username doesn't exist at that domain, you get a bounce-back message instead. That's why one wrong letter in an address means the email never arrives.
Examples of email addresses
| Address | What kind it is |
|---|---|
jordanlee88@gmail.com | Free personal address from Google |
maria.gonzalez@outlook.com | Free personal address from Microsoft |
sam@riveracatering.com | Business address on the company's own domain |
info@riveracatering.com | Role or shared address used by a team |
jordan.lee@school.edu | School or university address |
jordanlee88+shop@gmail.com | Plus address: still delivers to jordanlee88@gmail.com |
For a full list of the big free providers' domains, see our personal email domains list.
What's allowed in an email address
The short version:
- Safe characters before the @ are letters, numbers, dots, hyphens and underscores. The standard allows more, like
+, but some websites reject them. - No spaces, and only one @.
- Dots can't be first, last, or two in a row.
- Length: up to 64 characters before the @, and 254 for the whole address.
- Capital letters don't matter in practice:
Jordan.Lee@Gmail.comreaches the same inbox asjordan.lee@gmail.com.
All the details are in valid email address characters.
An email address is not...
- A website address.
www.gmail.comis a website.name@gmail.comis an email address. Email addresses never start with www or http. - Your password. Never share the password, even with someone who has your address.
- Your display name. The name people see in their inbox ("Jordan Lee") is set separately and can be anything. The address is what actually receives mail.
- An email account. The account is the login and the mailbox. One account can have several addresses, such as an alias.
How to get an email address
You have three main choices:
- A free address from a provider like Gmail, Outlook.com, Yahoo or iCloud. It takes a few minutes. Step-by-step: create a Gmail account or create a Yahoo account. Compare options in best free email services.
- A school or work address, which your school or employer creates for you.
- An address on your own domain, like you@yourname.com. It looks more professional for a business. See how to make a business email.
Need ideas for the username? Try our email name ideas.
Common mistakes when typing an address
- Domain typos:
gmial.com,gmail.co,hotmial.com,yahooo.com. - A comma instead of a dot:
jordan@gmail,com. - A space hidden at the start or end after copying and pasting.
- Missing letters in a long username.
Not sure an address is right? It flags typos and checks that the domain can receive mail.
Does it matter if you type capitals? See are email addresses case sensitive?
Questions people ask
- What is an email address?
- A unique address for a mailbox on the internet, written as name@domain, such as jordan.lee@gmail.com. Mail sent to it lands in that person's inbox.
- What does electronic mail mean?
- Electronic mail, or email, is a system for sending messages between computers over a network, and also the messages themselves.
- What is an example of an email address?
- jordan.lee@gmail.com is an example. jordan.lee is the username, @ means "at," and gmail.com is the domain.
- What are the parts of an email address called?
- The username (or local part) before the @, the @ sign, and the domain after it.
- Is an email address case-sensitive?
- In practice, no. Gmail, Outlook.com and almost every other provider treat capital and small letters the same.