Inspect, diagnose, and optimize
your email infrastructure
Eight production-grade diagnostic tools for SPF, DKIM, DMARC, DNS records,
IP reputation, reverse pointers, and client-safe email signatures.
DKIM Record Checker
Inspect domain email signatures, verify public key syntax, evaluate 1024 vs 2048-bit RSA key lengths, and prevent spoofing before emails leave your server.
- Tests selector DNS TXT record resolution
- Validates 2048-bit RSA cryptographic strength
- Parses v=DKIM1, k=rsa, and p= key tags
DMARC Policy Validator
Audit domain DMARC records against Google and Yahoo 2024 bulk sender rules. Inspect p=reject policy enforcement, aggregate report routing, and alignment pass rates.
- Verifies p=reject and quarantine protection
- Inspects rua and ruf reporting destinations
- Confirms Google & Yahoo bulk sender compliance
SPF Record Checker
Validate Sender Policy Framework mechanisms, resolve recursive include: chains, and calculate DNS lookups to stay safely below the RFC 10-query barrier.
- Counts DNS lookups against the strict 10-query limit
- Validates ip4, ip6, include, and all qualifiers
- Detects syntax mistakes and duplicate SPF entries
IP Blacklist Checker
Monitor your sending IP address or domain across 50+ major DNSBL/RBL databases including Spamhaus, Barracuda, and SORBS to protect your inbox rate.
- Real-time lookup across major DNSBL/RBL providers
- Monitors Spamhaus ZEN, Barracuda, and Spamcop
- Instant delisting advice for flagged mail servers
DNS Records Lookup
Query authoritative nameservers worldwide for A, AAAA, MX, TXT, CNAME, NS, SOA, and CAA records with sub-millisecond response time diagnostics.
- Queries 8 core DNS record types instantly
- Live resolution latency and nameserver breakdown
- Authoritative answer and TTL inspection
CNAME Alias Resolver
Trace canonical alias chains, verify custom branded subdomains for email tracking and custom sending domains, and prevent redirection loops.
- Follows multi-hop canonical alias chains
- Verifies custom tracking & click domain setup
- Detects circular redirection and broken targets
Reverse DNS (PTR) Lookup
Test Forward-Confirmed Reverse DNS (FCrDNS) alignment between mail server IPs and hostnames to satisfy strict Gmail and Microsoft inbound spam filters.
- Queries IPv4 and IPv6 PTR in-addr.arpa records
- Validates Forward-Confirmed Reverse DNS (FCrDNS)
- Essential for preventing mail rejection by Outlook & Gmail
Email Signature Generator
Design responsive, table-based HTML email signatures with social links, custom brand accents, avatar images, and one-click export for Gmail and Outlook.
- 100% table-based HTML compatible with all major email clients
- Custom brand accent colors and photo avatar integration
- Direct one-click rich clipboard copy for Gmail & Outlook
Ready to guarantee your inbox placement?
Send your emails through Mailofly’s sub-50ms routing engine with built-in SPF/DKIM authentication, automatic deliverability radar, and zero-downtime failover.