The address itself: what you can and cannot change
Every address here has two halves and a separator, and almost every question people ask turns out to be about one of the halves. This page is about the address as a string — what is allowed in it, what it may look like, and what happens when you push at the edges.
Questions about the service — how long the mailbox lives, who can read it, whether you can send — are answered in the general FAQ.
Which part actually matters?
The part after the @, almost always. The username is cosmetic: you may type anything you like and it changes nothing about whether the message arrives. The domain decides everything — whether mail can reach the mailbox at all, and whether the site you are signing up to will accept the address.
What can I put before the @?
Latin letters, digits, and dots, dashes and underscores inside the name. Practical advice rather than rules:
- Something that reads like a name works better than a random string.
anna.kovalenkoattracts no attention;x7k29fq3looks like exactly what it is, and some forms treat it accordingly. - Do not start or end with a dot, and do not use two in a row. It is invalid, and validators that check will reject the whole address.
- Case does not matter.
Annaandannaare the same mailbox.
Can I use a name someone else is already using?
Yes, and this is the part that surprises people. There is no registration, so there is nothing to claim. If you type an address someone else picked earlier, you open the same mailbox they did — and see the same messages.
test@, admin@ and john@ on a well-known domain are being opened by somebody else right now. Add something nobody would guess if the message matters.Why does the domain list keep changing?
Domains are added by people and lapse when those people stop paying for them. Nothing here is permanent by nature. If a domain you liked has gone, this is what usually happened to it.
Which domain should I pick?
Two rules, and they point in the same direction:
- Less famous is better. The best-known fake email domains are the first ones sign-up forms distrust.
- A country code helps with local services. An address that does not look foreign to an Italian shop or a German forum is refused less often — for no better reason than that it looks ordinary.
Whether a specific domain is accepting mail right now is a question with a definite answer: check it.
Can the address contain non-Latin letters or emoji?
The domain can, if you own one — mail servers translate such names into an ASCII form called punycode, and that form is what actually travels. The converter does the translation, and this explains which registries actually allow it. Expect sign-up forms to reject such addresses more often, and to accept the punycode form when they do.
How long may an address be?
Longer than you will ever need — the standard allows 64 characters before the @ — but forms in the wild frequently cap it far lower, sometimes at 20. If a form rejects a perfectly valid address without explanation, length is worth suspecting before anything else.
Can I keep the same address tomorrow?
While the mailbox lasts, yes: open the same address again and it is where you left it. Nothing is tied to your browser, so it works from another device too — which is the same fact as “anyone who knows the address can read it”, seen from the friendly side.
For an address that does not expire at all, use a domain of your own.