Check DNS MX records for up to 500 domains or URLs to identify their email service providers.
Paste up to 500 domains, email addresses, or website links. The tool strips protocols, paths, and www automatically.
Our high-speed DNS resolver queries mail exchanger records in asynchronous batches with zero rate limits.
View Google Workspace, Microsoft 365, Mimecast tags, copy TSV to clipboard, or export to CSV.
When scaling cold email campaigns or loading outbound lists into Salesloft, Outreach, or Instantly, sending messages to unverified domains destroys domain sender reputation. An MX record (Mail Exchanger) is the authoritative DNS entry that tells the internet which server is authorized to receive email for that domain.
If an organization shuts down or abandons a domain, its MX records disappear. Blasting cold emails to domains without MX records results in immediate hard bounces. Keeping bounce rates strictly below 2% is mandatory to avoid Google and Outlook spam filters.
Deliverability studies prove that Google-to-Google and Microsoft-to-Microsoft email routing consistently outperforms cross-provider sending. Grouping target accounts by email provider allows you to dynamically route emails through matched sending tenants.
| Email Provider | MX Hostname Pattern | Deliverability Strategy |
|---|---|---|
| Google Workspace | aspmx.l.google.com | Route from Google sending domains. Avoid excessive tracking pixels. |
| Microsoft 365 (Office 365) | *.mail.protection.outlook.com | Route from M365 tenants. Strictly maintain SPF, DKIM, DMARC alignment. |
| Proofpoint Enterprise | *.pphosted.com | Strict spam gateway. Send 100% plain text without external links. |
| Mimecast | *.mimecast.com | Graylisting enabled. Always schedule automated follow-ups. |
| Zoho Mail | mx.zoho.com | Standard corporate deliverability rules apply. |
An MX check verifies that the domain has an active email server configured to receive mail. Full email verification takes this a step further by simulating an SMTP handshake with that server to confirm whether a specific mailbox (e.g. [email protected]) exists, is full, or is configured as a catch-all.
Those numbers represent priority or preference. Mail servers always attempt to deliver to the server with the lowest preference number first (e.g. priority 10). If that server is offline or unreachable, it falls back to the higher numbered servers (priority 20, 30, etc.).
Yes. This free web tool allows anyone to check up to 500 domains simultaneously with no API keys, accounts, or credit cards required.
Immediately remove any contacts associated with that domain from your outreach sequence or CRM pipeline. Sending emails to domains without MX records results in an instant hard bounce that damages your sender score.
Read our tactical guide on bulk MX records, ESP segregation, and cold outreach inbox placement.
Enrichverx performs multi-layer waterfall verification, catch-all detection, and real-time SMTP handshakes to guarantee zero bounces for your revenue team.