Email & DNS tools
Build and inspect mail authentication, transport-security and everyday DNS records without claiming to query live DNS.
Email & DNS
SPF Record Generator
Build an SPF TXT value from the senders you explicitly authorise.
Email & DNSEmail Address Extractor
Extract ordinary email addresses and occurrence counts from supplied text.
Email & DNSEmail Header Analyser
Inspect supplied email headers and the claimed delivery route.
Email & DNSSPF Record Analyser
Inspect an SPF TXT value, its mechanisms and direct DNS-querying terms.
Email & DNSSPF Flattening Planner
Plan a conservative SPF include expansion from records you supply.
Email & DNSDMARC Record Builder
Build a current DMARC TXT policy for a domain.
Email & DNSDMARC Record Analyser
Explain a supplied DMARC policy and its effective defaults.
Email & DNSDKIM Public Key Record Analyser
Inspect the structure of a DKIM selector public-key record.
Email & DNSDMARC Alignment Checker
Check strict or relaxed DMARC identifier alignment from supplied domains.
Email & DNSDMARC Aggregate Report Analyser
Summarise message counts and outcomes in a DMARC aggregate XML report.
Email & DNSMicrosoft 365 Email DNS Checklist
Build a Microsoft 365 email DNS checklist using tenant values you provide.
Email & DNSAuthentication-Results Header Analyser
Read method outcomes and properties from an Authentication-Results header.
Email & DNSDNS Record Builder
Build a reviewable DNS zone-file record from common fields.
Email & DNSReverse DNS / PTR Name Builder
Convert an IP address to the DNS owner name used for a PTR record.
Email & DNSMX Priority Planner
Put MX records into the order an SMTP sender considers them.
Email & DNSSRV Record Builder
Build a service-location record with priority, weight, port and target.
Email & DNSCAA Record Builder
Build a CAA property that constrains certificate issuance for a domain.
Email & DNSDNS TTL Change Planner
Plan when to lower and later restore a DNS cache lifetime around a change.
Email & DNSSOA Serial Generator
Create a readable SOA serial using the YYYYMMDDnn convention.
Email & DNSMTA-STS Policy Builder
Build the MTA-STS discovery record and HTTPS policy body.
Email & DNSSMTP TLS Reporting Record Builder
Build a DNS record that requests aggregate SMTP TLS reports.
Email & DNSSMTP Enhanced Status Explainer
Interpret an enhanced SMTP delivery status code and choose a response.