Split email addresses into username and domain columns
In short: Adds username, username without the +tag, the tag, domain, subdomain, registrable domain (acme.co.uk) and domain ending columns to every row of a list or CSV. Limit: It splits text; it doesn't check that the address or domain works.
To split an email address, everything before the last @ is the username and everything after it is the domain: [email protected] splits into jane+news and mail.acme.co.uk. Paste a list or upload a CSV and this tool adds those columns to every row, plus the username without its +tag, the subdomain, the registrable domain (acme.co.uk) and the ending (co.uk).
Price: this tool is free. Checking a whole email list is from $9/mo, and the first 100 checks are free with Google, no card. See pricing
Sample result
[email protected] splits into bob, tag webinar and domain contoso-example.co.uk.
- Address
- [email protected]
- Username
- bob+webinar
- Registrable domain
- contoso-example.co.uk
What this means for you
Get username, tag, domain and company domain columns without a formula.
- Username and domain columns
- +tag split off
- Subdomain and registrable domain
- Every original column kept
- Split
- Domain
- CSV
By SimpleVerifier Team · Last updated · Runs in your browser; nothing you paste is sent to us
How do I separate the username and domain of email addresses?
- Paste addresses or upload a CSV export. The email column is found automatically and every column is kept.
- Choose the tag separator: + for most providers, - for some self-hosted servers, or none.
- Press Split the addresses.
- Download the CSV with seven new columns, or copy just the usernames or the domains.
Example
- You enter
- Five rows including
[email protected],[email protected]and[email protected]. - You get
[email protected]splits into usernamebob+webinar, without tagbob, tagwebinar, domaincontoso-example.co.uk, registrable domaincontoso-example.co.ukand endingco.uk.[email protected]gets subdomainmail. The row that isn't an address keeps empty columns.- Limits
- Runs in your browser with no row cap; an uploaded file can be up to 25 MB.
How do I split an email at the @ in Excel or Google Sheets?
In Excel 365, =TEXTBEFORE(A2,"@",-1) gives the username and =TEXTAFTER(A2,"@",-1) the domain; the -1 splits at the last @, which matters for the rare quoted addresses that contain one (RFC 5322). In older Excel, use =LEFT(A2,FIND("@",A2)-1) and =MID(A2,FIND("@",A2)+1,255), or Data > Text to Columns with @ as the delimiter. In Google Sheets, =SPLIT(A2,"@") fills both columns.
Those formulas stop at username and domain. This tool also separates the +tag (the part after + that Gmail and Microsoft 365 deliver to the base mailbox), and splits the domain against the Public Suffix List, so mail.acme.co.uk gives the subdomain mail, the registrable domain acme.co.uk and the ending co.uk, which a split at the last dot gets wrong.
What is the registrable domain used for?
It's the company's domain without mail or regional subdomains, the name a company registers. Grouping on it puts eu.acme.com and acme.com together, which is what you want when limiting contacts per company, matching leads to accounts in a CRM, or turning domains into company names. The email to domain extractor counts addresses per domain if that's the question.
Is this better than TEXTBEFORE and TEXTAFTER?
| This tool | Excel formulas | |
|---|---|---|
| Username and domain | Yes | Yes |
| +tag separated | Yes | Another formula |
| Registrable domain (acme.co.uk) | Yes, Public Suffix List | Not reliably |
| Rows that aren't addresses | Kept, columns empty | #VALUE! errors |
Excel 365: =TEXTBEFORE(A2,"@",-1) and =TEXTAFTER(A2,"@",-1). Google Sheets: =SPLIT(A2,"@").
Who uses this tool, and for what?
- Sales ops
- Add a registrable domain column to a lead export to match leads to accounts in the CRM.
- SaaS teams
- Split signups into username and tag to see which +tags people sign up with.
- Analysts
- Turn an email column into domain and ending columns for a pivot table by company or country.
What can’t this tool tell you?
- It splits text; it doesn't check that the address or domain works.
- The registrable domain uses the ICANN section of the Public Suffix List, so private suffixes such as github.io aren't split off.
- Only one tag separator is applied per run.
Common questions
- What is the username part of an email address called?
- The local part, in the RFCs. Mail services call it the username or mailbox name.
- Is the username case-sensitive?
- RFC 5321 allows servers to treat it as case-sensitive, but almost none do. The domain is never case-sensitive. The tool keeps the username as written and lower-cases the domain.
- What happens to rows that aren't addresses?
- They're kept, with the new columns left empty.
- Can I split on a hyphen instead of a plus?
- Yes. Some self-hosted servers use - or another character for subaddressing; choose it from the separator list.
- Is anything uploaded?
- No. It runs in your browser, and files can be up to 25 MB.
Sources
A tidy list can still be full of dead addresses.
Extracting, deduplicating and syntax checks all work on the text of an address. None of them can tell whether the mailbox exists. Only the server that hosts it can answer that, through an SMTP check, and that is what the paid product does.
- Upload the cleaned file as it is: CSVs up to 100,000 rows
- A real SMTP mailbox check on every row, with catch-all detection
- Small list? Starter at $9/mo covers 2,500 emails a month, cancel anytime
Plans from $9 a month, cancel anytime, no contract. Sign in with Google and your first 100 email checks are free, no card. The free tools stay free either way.