How to Check Gmail Usernames Against Google's Rules
A Gmail username is valid when it is 6 to 30 characters long and uses only letters, numbers and periods, with no two periods in a row and no period at the start or end. The Gmail username rules checker tests a whole list of names against those rules and says which rule each one breaks.
It checks the format. It doesn't ask Google whether the name is taken.
The rules
Google's Gmail help lists what a username can contain: letters, numbers and periods. It can't contain an ampersand, equals sign, underscore, apostrophe, dash, plus sign, comma or brackets, can't have more than one period in a row, and can't start or end with a period. Capitals are ignored.
Why a valid name can still fail
- The name may already be taken.
- Gmail ignores periods, so
jane.doeandjanedoeare the same inbox. - Google never reissues the name of a deleted account and holds some names back.
Only Google's sign-up page can confirm a name is available.
The by-hand way
- Count the characters: 6 to 30.
- Scan for anything that isn't a letter, number or period.
- Look for
..and for a period at either end.
Step 1: paste the names
Paste usernames or Gmail addresses, one per line. A name without an @ is treated as @gmail.com.
Step 2: read each row
| Result | What it means |
|---|---|
| Valid format | The name passes every rule |
| Under 6 or over 30 characters | The length is outside Gmail's range |
| Character Gmail doesn't allow | The character is named in the row |
| Two periods in a row, or a period at the edge | A period rule is broken |
| Not a Gmail address | The domain is something else |
What this check cannot do
- It can't tell you whether a name is taken.
- It can't know if Google changes its rules; Google's help page is the final word.
To see which valid-format names already receive mail, check the addresses: the first 100 checks are free with a Google sign-in, no card. To reduce a list to one row per inbox, use the Gmail address normalizer.
Try it now
Paste your names into the Gmail username rules checker at simpleverifier.com.
Common questions
How many characters can a Gmail username have?
Between 6 and 30 characters.
Can a Gmail username have an underscore or a dash?
No. Google's rules allow letters, numbers and periods only.
Does a valid format mean the name is free?
No. It means the name is allowed to exist. It can still be taken, and only Google's sign-up page can confirm it is free.
Check your list before you send
Real mailbox checks over SMTP, and nothing is sent to the address. Sign in with Google and your first 100 email checks are free, no card. Plans for bigger lists are on the pricing page.