MX Record Lookup - Check Mail Server Configuration
No logs stored • Server-side processing
Find mail servers, priorities, IP addresses, and email providers for any domain. Check SPF, DKIM, DMARC authentication with security scoring.
Free Online MX Record Checker
Enter a domain above to get started
We'll show you A, AAAA, MX, CNAME, TXT, NS, SOA, and CAA records
What is MX Lookup?
MX Lookup queries DNS to find the Mail Exchange records for any domain. These records tell email servers where to deliver messages—showing mail server hostnames, priority values, and which email provider (Google Workspace, Microsoft 365, Zoho, etc.) handles the domain's email. Our tool goes further by resolving IP addresses and analyzing email authentication.
What You'll Discover
Can Find
- Mail server hostnames with priority values
- Resolved IPv4 and IPv6 addresses for each server
- Email provider identification (15+ providers)
- SPF, DKIM, DMARC authentication status
- Email security score (0-100) with grade
- RBL blacklist status for mail servers
Cannot Find
- Actual email deliverability (we check DNS, not SMTP)
- Email content or headers
- Whether specific emails were delivered
- Private or internal mail server configurations
How to Check MX Records
Find mail server configuration for any domain in seconds
Enter the Domain
Type the domain name you want to check (e.g., gmail.com). Protocols like https:// and www prefixes are automatically cleaned.
Click Lookup
We query DNS servers to retrieve all MX records. Each mail server hostname is resolved to IPv4 and IPv6 addresses in parallel.
View Mail Servers
See results sorted by priority (lower numbers = higher preference). The 'Primary' badge marks the main mail server. Provider badges show Google Workspace, Microsoft 365, etc.
Check Email Authentication
Review SPF, DKIM, and DMARC status with recommendations. Our security score (0-100) grades your email authentication from A to F.
Understanding Your MX Lookup Results
What each field in your MX records reveals
Priority
The preference value for mail routing. Lower numbers have HIGHER priority—email servers try priority 5 before priority 10. If the primary server is down, mail routes to backup servers with higher priority numbers.
5 (Primary), 10 (Backup)
Mail Server
The fully qualified domain name (FQDN) of the mail exchange server. This is the hostname that receives email for the domain. For gmail.com, this might be 'gmail-smtp-in.l.google.com'.
aspmx.l.google.com
Email Provider
We auto-detect 15+ email providers by matching MX hostname patterns. Google Workspace, Microsoft 365, Zoho, Proofpoint, Mimecast, Barracuda, and more are identified instantly with visual badges.
Google Workspace
IPv4 Address
The resolved A record for the mail server hostname. This is the actual IP address where email connections are made. Useful for firewall configuration and connectivity troubleshooting.
142.250.115.26
IPv6 Address
The resolved AAAA record showing the IPv6 address. Modern mail servers often support both IPv4 and IPv6. Not all servers have IPv6 configured.
2607:f8b0:4003:c00::1a
SPF Status
Sender Policy Framework record status. SPF specifies which servers are authorized to send email for the domain. A green checkmark means SPF is configured; we also show the actual record and policy (-all, ~all, +all).
v=spf1 include:_spf.google.com ~all
DMARC Policy
Domain-based Message Authentication policy. DMARC tells receiving servers what to do with emails that fail SPF/DKIM checks. Policies are 'none' (monitor), 'quarantine' (spam folder), or 'reject' (block).
p=reject
Security Score
Our 0-100 score grading email authentication. SPF contributes up to 40 points (30 for existence, 10 for strict -all policy). DMARC contributes up to 60 points (30 for existence, 30 for reject policy). Score 90+ = A, 75-89 = B, 60-74 = C, 40-59 = D, below 40 = F.
85/100 (Grade B)
Why Choose Our MX Lookup Tool
More than just MX records—complete email configuration analysis
15+ Email Provider Detection
Instantly identify Google Workspace, Microsoft 365, Zoho, Proofpoint, Mimecast, Barracuda, Cloudflare, Amazon SES, SendGrid, and more from MX patterns. Visual badges show the provider at a glance.
IPv4 & IPv6 Resolution
Every MX hostname is resolved to its IP addresses automatically. See both IPv4 (A record) and IPv6 (AAAA record) addresses to verify reachability and configure firewalls.
Email Authentication Analysis
SPF, DKIM, and DMARC records analyzed together with your MX data. Get a security score (0-100) and letter grade (A-F) with specific recommendations to improve deliverability.
RBL Blacklist Checking
Mail server IPs are checked against major blacklists: Spamhaus ZEN, Barracuda RBL, SORBS, and SpamCop. Critical for diagnosing email deliverability problems.
All DNS Record Types
MX tab is active by default, but A, AAAA, TXT, NS, SOA, and CAA records are available via tabs. One lookup gives you the complete DNS picture.
Export to JSON/CSV/TXT
Download your MX lookup results in multiple formats. JSON for APIs and automation, CSV for spreadsheets, plain text for documentation and sharing.
When You Need MX Lookup
Common scenarios where MX record checking is essential
Email Deliverability Troubleshooting
Not receiving emails? Check MX records to verify mail servers are correctly configured. Our IP resolution shows if servers are reachable, and RBL checking reveals if they're blacklisted.
Email Provider Migration
Moving from Gmail to Microsoft 365? Or self-hosted to Google Workspace? Verify MX records before and after migration to ensure email routes to the new provider correctly.
Security Audits
Ensure backup MX servers exist for redundancy. Check for unauthorized mail servers. Verify SPF, DKIM, and DMARC are properly configured to prevent spoofing and phishing.
Competitive Intelligence
Discover which email infrastructure competitors use. Are they on Google Workspace, Microsoft 365, or using enterprise security like Proofpoint or Mimecast?
How MX Records Work
Understanding MX records helps you manage email routing and troubleshoot delivery issues.
What are MX Records?
MX (Mail Exchange) records are DNS records that specify the mail servers responsible for receiving email for a domain. When someone sends an email to user@example.com, their mail server queries example.com's MX records to find where to deliver the message. Each MX record has two parts: a priority number and a hostname.
How MX Priority Works
The priority value determines mail routing preference. Lower numbers have HIGHER priority—email servers always try the lowest priority first. If that server is unavailable (timeout, connection refused), mail routes to the next lowest priority. Most domains have 2-5 MX records for redundancy. Best practice: primary server at priority 10, backup at 20, tertiary at 30.
Email Provider Detection
We identify email providers by matching MX hostnames against known patterns. For example, 'aspmx.l.google.com' indicates Google Workspace, while '*.mail.protection.outlook.com' indicates Microsoft 365. We detect 15+ providers including Zoho, Proofpoint, Mimecast, Barracuda, Cloudflare Email, Amazon SES, SendGrid, Mailgun, and others.
Security Score Calculation
Our email security score ranges 0-100 based on SPF and DMARC configuration. SPF contributes up to 40 points: 30 for existence, plus 10 for strict '-all' policy (or 5 for '~all', minus 10 for insecure '+all'). DMARC contributes up to 60 points: 30 for existence, plus 30 for 'reject' policy (20 for 'quarantine', 5 for 'none'). Grades: A (90+), B (75-89), C (60-74), D (40-59), F (<40).
MX Lookup Specifications
- Record Types
- MX (default), A, AAAA, TXT, NS, SOA, CAA
- IP Resolution
- Automatic IPv4 and IPv6 for each MX
- Provider Detection
- 15+ email providers identified
- Email Authentication
- SPF, DKIM (25 selectors), DMARC
- RBL Checking
- Spamhaus, Barracuda, SORBS, SpamCop
- Response Time
- < 500ms (cached: < 50ms)
- Cache Duration
- 5 minutes (300 seconds)
- Export Formats
- JSON, CSV, Plain Text
- API Access
- REST API at /api/v1/dns-lookup
Frequently Asked Questions
What is an MX record and why does it matter?
An MX (Mail Exchange) record is a DNS record that specifies the mail servers responsible for receiving email for your domain. Without proper MX records, emails sent to your domain won't be delivered. The priority values determine which server receives email first—lower numbers have higher preference.
How do I read MX record priorities?
Lower priority numbers have HIGHER preference. An MX record with priority 5 is tried before priority 10. If the first server is unavailable, email routes to the next priority. Our tool marks the lowest priority server as 'Primary' with a badge. Most domains use priorities like 10, 20, 30 for primary, backup, and tertiary servers.
Can a domain have multiple MX records?
Yes, and it's recommended. Multiple MX records with different priorities provide redundancy. If your primary mail server is down, email can still be delivered to backup servers. Most organizations configure 2-5 MX records. We show a status indicator when backup servers are configured.
What does 'Primary' MX mean?
The 'Primary' badge indicates the MX record with the lowest priority number (highest preference). This is the mail server that receives email first under normal circumstances. Other servers act as backups if the primary is unavailable.
How long do MX record changes take to propagate?
MX record changes typically propagate within 1-4 hours globally, but the TTL (Time To Live) value determines how long DNS servers cache the old record. If you're changing email providers, set a low TTL (300 seconds) 24 hours before the change to speed up propagation.
Why does the tool show IP addresses for MX records?
We automatically resolve each MX hostname to its IPv4 and IPv6 addresses. This helps verify mail servers are reachable and shows the actual servers behind the hostname. It's useful for troubleshooting connectivity issues and firewall configuration.
What if no MX records are found?
If no MX records exist, email servers will try to deliver directly to the domain's A record as a fallback. However, this is bad practice—proper email hosting always uses dedicated MX records. A missing MX usually indicates the domain isn't configured for email or there's a DNS misconfiguration.
How is the email security score calculated?
SPF contributes up to 40 points (30 for existence, 10 more for strict '-all' policy). DMARC contributes up to 60 points (30 for existence, up to 30 more based on policy—'reject' = 30, 'quarantine' = 20, 'none' = 5). The grade is A (90+), B (75-89), C (60-74), D (40-59), F (<40).
Check Any Domain's Mail Server Configuration
Enter a domain above to see MX records, email providers, and authentication status. Free, fast, no registration required.
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