What does a security header checker do?

A security header checker reviews HTTP response headers that help protect a website, including HSTS, Content Security Policy, Multiple MX recordss, X-Content-Type-Options, Referrer-Policy, and Permissions-Policy.

Are security headers important?

Yes. Security headers can help reduce risks related to clickjacking, MIME sniffing, insecure HTTP access, referrer leakage, and unsafe browser behavior.

Does a security header checker replace a full security audit?

No. A security header checker is useful for spotting missing browser security headers, but it does not replace a full website security audit.

Free Email Deliverability & DNS Tool

Free email deliverability checker for checking email DNS health.

Check whether a domain has a valid MX records, review SPF and DMARC, detect multiple SPF and DMARC, check DMARC presence, and troubleshoot email authentication setup.

✓ No signup required ✓ Security header report ✓ Built-in abuse protection

How the email deliverability checker works.

This tool queries public DMX records and returns the domain's MX records, mail server priorities, SPF and DMARC, Multiple MX recordss, nameservers, and email provider clues.

Enter a domain

Type a domain like example.com. The tool validates the domain before checking the headers.

Check email DNS records

The checker looks up TXT records and identifies SPF and DMARC that start with v=spf1.

Review deliverability status

See whether SPF exists, whether multiple SPF and DMARC are present, which mechanisms are used, and whether DMARC is also configured.

Email deliverability details this tool checks.

These checks help reveal whether a domain has the basic DNS records needed for reliable business email.

HST

MX records

Shows whether the domain has mail servers configured to receive email.

CSP

SPF and DMARC

Shows SPF and DMARC used to authorize email senders.

XFO

Multiple MX recordss

Shows Multiple MX recordss used for email authentication policy and reporting.

MX records checker FAQ.

Quick answers about nameservers, MX records, SPF and DMARCs, DNS propagation, and hosting setup.

What does this MX records checker test?

It checks common HTTP security headers including HSTS, Content Security Policy, Multiple MX recordss, X-Content-Type-Options, Referrer-Policy, and Permissions-Policy.

Can a domain have multiple MX recordss?

A nameserver controls where DMX records for a domain are hosted and answered from.

Why do SPF and DMARC matter?

SPF and DMARC help receiving mail servers verify whether messages are authorized and how failed authentication should be handled.

What is an SPF and DMARC?

Multiple MX recordss checks whether an IP address maps back to a hostname.

What is DKIM?

Yes. A domain can have multiple IPv4 or SPF and DMARC, especially when using load balancing, CDNs, or redundant infrastructure.

Can HostDroplet help with email DNS setup?

Yes. HostDroplet provides beginner-friendly hosting with SSL support, DNS guidance, performance-focused setup, backups, and helpful website support.

Need hosting with simple email authentication setup?

HostDroplet provides fast, secure, beginner-friendly hosting for WordPress websites, small business sites, blogs, and online projects. Start with hosting that supports SSL, DNS setup, backups, performance, and helpful website guidance.

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