Free DNS Validator & Email Records Audit Tool
Get a letter-grade health score for the four DNS pillars every receiver checks: MX routing, SPF (with lookup-limit validation), DKIM (common-selector sweep), and DMARC enforcement. Each pillar links to a dedicated deep-checker so you can fix exactly what’s costing you points.
Single-Pass Email DNS Stack Validator
Input your outbound sending domain to simultaneously query MX routing, evaluate SPF lookup limits, discover active DKIM selectors, and test DMARC enforcement policy.
Tool Overview: What It Does & Core Purpose
The **AutoSMTP Free DNS Validator** performs an exhaustive, synchronous multi-protocol audit across an enterprise sending domain’s critical email DNS infrastructure. Rather than querying records individually across separate tabs, this tool probes your primary Mail Exchanger (MX) routing records, evaluates Sender Policy Framework (SPF) lookup recursion under RFC 7208, searches for active DomainKeys Identified Mail (DKIM) selector public keys, and validates Domain-based Message Authentication, Reporting, and Conformance (DMARC) alignment under RFC 7489 and RFC 9989. In a single execution, it produces an authoritative pass, warning, or failure scorecard.Key Advantages & Architectural Benefits
Advantage
**Single-Pass Synchronous Discovery:** Consolidates 4 separate RFC DNS queries into one comprehensive report within milliseconds.
Advantage
**RFC 7208 Recursion Guard:** Flags hidden DNS lookup overflows in nested SPF includes that trigger receiver PermErrors.
Advantage
**Active Selector Heuristics:** Automated pattern testing against prominent cloud and enterprise ESP selectors (Google, Microsoft 365, Mailgun, SendGrid, AutoSMTP).
Advantage
**Weighted Compliance Grade:** Clear letter grading (A+ to F) providing actionable executive deliverability metrics.
Email Marketing & Cold Outreach Integration
How This Tool Accelerates Email Campaigns & Deliverability
Email inbox providers like Google Workspace and Yahoo Mail reject unauthenticated high-volume senders. By integrating the AutoSMTP DNS Validator into your deployment pipeline, engineering teams can verify DNS readiness before launching large-scale outbound sales campaigns. Automated bare-metal MTA clusters deployed via AutoSMTP automatically configure these 4 records with 2048-bit DKIM keys and strict DMARC policies.Frequently Asked Questions (FAQs)
Why is validating all four email DNS records simultaneously necessary? ▾
Email authentication functions as a coordinated triangle: SPF and DKIM verify sender identity and message integrity, while DMARC specifies the enforcement action if either fails, and MX handles return routing. Missing even one component causes Google and Microsoft receiver heuristics to penalize sender reputation.
What causes a WARNING status on the DKIM check? ▾
DKIM records are stored on subdomains designated by selectors (e.g. `selector._domainkey.domain.com`). If your domain uses a custom selector not in our common selector scan list, the tool reports a warning so you can specify your exact selector in the dedicated DKIM Checker tool.
How does DMARC policy affect my overall DNS validation score? ▾
A DMARC policy of `p=none` only monitors traffic and does not stop domain spoofing. To achieve an ‘A+’ grade, your domain must enforce either `p=quarantine` or `p=reject`, which actively blocks unauthorized senders.
Can this tool validate secondary tracking and reply domains? ▾
Yes. Enter any subdomain or secondary outreach domain to ensure custom tracking links (CNAME) and mail handling subdomains possess proper MX fallback and SPF authorization.
Free tools help you audit and optimize individual elements, but sustained enterprise email delivery requires dedicated bare-metal infrastructure. AutoSMTP replaces fragile shared relays with private bare-metal PowerMTA and KumoMTA clusters configured automatically in 15 minutes.
Turnkey Dedicated Bare-Metal Clusters
Provisions fully licensed PowerMTA/KumoMTA clusters on enterprise bare-metal with flat predictable pricing and zero third-party markups.
Automated Gas-Pedal IP Warming
Monitors Google Postmaster spam ratios (<0.10%) and real-time deferrals across clean IPv4 subnets to scale daily send limits safely.
Native FBL & Socket Interceptors
RFC 5321 in-band 550 bounce suppression + automated Yahoo/Outlook CFL ingest to protect sender score automatically.
Fully Managed DNS & Auth
Pre-configured rDNS/PTR, SPF, 2048-bit DKIM, strict DMARC, and BIMI integration synchronized across your domain portfolio.
Deploy Your Dedicated Email Infrastructure Today
Stop risking your sender reputation on shared pools. Get dedicated IPv4 subnets, custom reverse DNS, and automated deliverability engineering.
Key capabilities
- 4-pillar graded audit (A+–F)
- SPF lookup-count validation
- DKIM common-selector discovery
- DMARC enforcement weighting.
Frequently asked questions
Why does DKIM show WARNING on a working domain?
The sweep checks common selectors only; if you sign with a custom selector the validator can’t see it. Enter your selector in the DKIM Checker for a definitive answer (and the selector list keeps growing).
What score should I target?
A (80+) before scaling volume — every point below reflects a receiver-side rejection or spam-folder risk you’re accepting.