MX Record Lookup – Mail Server DNS Checker
See which mail servers accept email for a domain (MX records).
Introduction
Email delivery starts in DNS long before a message reaches an inbox. MX records advertise which servers accept inbound SMTP for your domain, and sending mail systems consult those records on every delivery attempt.
A wrong or missing MX record sends legitimate mail to dead hosts or legacy providers, while correct MX publishing is the foundation of reliable business email.
This MX record lookup on VSPIC shows live mail exchanger hostnames and priorities so you can confirm routing during setup, migration, and incident response.
How to use this mx record lookup tool
- Enter the domain that receives email (for example example.com — not a mailbox username).
- Click Lookup MX Records to query authoritative DNS.
- The tool returns MX answers filtered to mail exchanger records only.
- Review the table with Host, mail server Value, and TTL.
- Compare priority numbers — lower values are tried first by sending servers.
- Follow up with TXT Record Lookup for SPF, DKIM, and DMARC on the same domain.
What Is MX Record
MX — Mail Exchanger — is a DNS record type that pairs a priority number with a target hostname. The priority is not a port or weight in the load-balancer sense; it is an ordering hint for SMTP clients choosing where to deliver.
The MX target hostname must itself resolve to IP addresses via A or AAAA records. MX does not embed IPs directly.
A domain that intentionally does not receive mail may publish a null MX (MX pointing to .) per RFC conventions to signal that SMTP should not be attempted.
How Email Routing Works
When a sender dispatches mail to user@example.com, the sender's MTA looks up MX records for example.com. It sorts by priority and attempts SMTP connections to each exchanger in order until one accepts the message.
If the lowest-priority server is down, senders retry backups with higher priority numbers. Retry schedules and queue behavior depend on the sending platform, but MX ordering is universal.
Outbound mail from your users uses different mechanisms — submission on port 587 or provider APIs — but inbound delivery always keys off MX at the recipient domain.
MX Priority Explained
Priority is an integer where smaller means more preferred. An MX of 10 is tried before an MX of 20. Multiple records may share the same priority for load sharing among equals.
Providers often publish a primary exchanger at priority 0 or 10 and backup hosts at 20 or higher. Always compare the numeric column, not alphabetical hostname order.
Changing priorities without updating hostnames can silently shift mail volume between clusters — document intended priority maps in change tickets.
How To Use
- Enter the mail-receiving domain (the part after @ in addresses).
- Click Lookup MX Records.
- Read each Value column for the mail exchanger hostname.
- Sort mentally by priority — lower numbers win.
- Note TTL to estimate propagation delay after edits.
- Cross-check TXT authentication records before closing migration tickets.
Examples
| Scenario | Typical MX pattern |
|---|---|
| Business email suite | One primary MX hostname at priority 0–10 |
| Redundant provider | Two MX with same priority for load share |
| Migration window | Old and new MX coexist briefly with different priorities |
| Parked domain | No MX or provider parking MX |
| Transactional subdomain | Separate MX on mail.example.com |
Benefits
- Mail-specific view without unrelated DNS clutter
- Priority visible for failover planning
- Fast validation during provider switches
- Copy exchanger hostnames for support tickets
- Works alongside TXT and SPF tools on this site
- No CLI or account required
Email Troubleshooting
Mail not arriving
- Confirm MX points to the active provider, not a decommissioned host.
- Verify MX target hostnames resolve with A/AAAA lookup.
- Check SPF/DKIM/DMARC after MX is correct.
Split delivery after migration
- Stale MX with equal or better priority still attracts traffic.
- Remove old MX once cutover is verified.
Priority confusion
- Lower number = preferred. Do not assume alphabetical order.
- Document which hostname is primary in runbooks.
Best Practices
- Publish MX only to provider-documented hostnames
- Lower TTL before cutovers; restore after stability
- Remove legacy MX when migration completes
- Verify authentication TXT records in the same change window
- Test inbound delivery with a real message after DNS updates
- Keep registrar glue and NS delegation aligned with DNS host
Common Email Configuration Errors
- MX target hostname without working A/AAAA records
- Pointing MX to the web server instead of the mail provider
- Leaving old provider MX at better priority than new hosts
- Missing SPF include for the new sending infrastructure
- Forgetting DMARC when tightening SPF
- Using CNAME targets for MX against best practices
Disclaimer
MX records describe intended inbound routing only. Delivery success also depends on provider configuration, reputation, authentication records, and network reachability.
mx record lookup — frequently asked questions
It queries DNS for MX records and lists the mail exchanger hostnames that accept email for a domain, with priorities.
An MX (Mail Exchanger) record points to the hostname of a server that receives SMTP mail for the domain, plus a priority value.
Sending servers sort MX records by priority ascending. The lowest number is preferred; equal or higher numbers are fallbacks.
Yes. Multiple MX entries with different priorities provide redundancy and load distribution across mail providers.
MX targets must be hostnames, not bare IP addresses. Those hostnames resolve via A or AAAA records separately.
Check SPF, DKIM, DMARC, firewall port 25, and provider-side acceptance rules. MX alone does not guarantee delivery.
Yes, once traffic is stable. Leaving stale MX records can split mail between old and new providers.
Common values are 300–3600 seconds. Lower TTL before migrations speeds rollback if something goes wrong.
Subdomains need their own MX unless mail routing policies say otherwise. Always query the exact domain that receives mail.
This tool shows only MX records for a quick mail-routing answer without other DNS types.
Standards discourage MX targets that are CNAME aliases. Use a hostname with direct A/AAAA instead.
The domain may not accept mail, use a child domain for mail, or DNS may be misconfigured. Verify NS delegation too.
Yes. VSPIC provides MX lookups at no cost.
Before and after email provider migrations, when mail stops arriving, and during domain onboarding audits.
Yes. SPF, DKIM, and DMARC live in TXT records. Use TXT Record Lookup or the SPF DKIM DMARC Checker after MX verification.
Next step for mx record lookup
Continue with txt record lookup on VSPIC.
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