Runs in your browser using Google Public DNS. We do not store the domains you check.
Get your sending domains and inboxes set up for you
B2BX Infra sets up Google Workspace and Microsoft 365 inboxes on new domains with SPF, DKIM and DMARC already in place, ready to warm up.
What each check means
| Record | What it does | What happens if it is missing |
|---|---|---|
| MX | Tells the internet which server receives mail for your domain | Prospects' replies bounce, so you lose the very replies you are paying for |
| SPF | Lists the services allowed to send email as your domain | Receivers cannot tell your real emails from forgeries, so more of them go to spam |
| DKIM | Adds a signature that proves the email was not changed on the way | Emails are harder to trust and DMARC cannot pass on DKIM |
| DMARC | Tells receivers what to do when SPF or DKIM fail, and where to send reports | Google's sender guidelines require it for bulk senders; without it, deliverability suffers |
How to use the results
- Red (Missing): fix before you send anything. Copy the example record shown and add it in your domain provider's DNS settings.
- Amber (Check): works, but could be stronger. A DMARC policy of
p=noneis fine while you warm up; tighten it once reports look clean. - Green (Pass): the record exists and looks valid. Re-check after any change to your email provider or sending tool.
Never run cold email from your main company domain. Use separate sending domains, each with its own SPF, DKIM and DMARC, and check every one of them here. If you want domains and inboxes set up for you with every record already in place, use B2BX Infra, or work out how many domains you need with the infrastructure calculator.
Frequently asked questions
What is a DKIM selector?
It is the name your email provider uses for your DKIM key, for example "google" for Google Workspace or "selector1" for Microsoft 365. You find it in your provider's DKIM settings. If you leave the box empty, the checker tries the most common selectors.
Is a DMARC policy of p=none enough?
For meeting Google's bulk-sender requirement, yes: a DMARC record with p=none is accepted. It only monitors, though. Once your reports show your real senders passing, move to p=quarantine for better protection.
Why does my domain have two SPF records?
Usually because a new tool added its own record instead of joining the existing one. Two SPF records make SPF fail. Merge them into one record that starts with v=spf1 and includes every sender.
Does this tool store the domains I check?
No. The checks run in your browser against Google Public DNS. B2BXclusive does not receive or store the domains you enter.