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NetInsight

The complete network, DNS, email & domain diagnostic platform for engineers who care about uptime and deliverability.

DNS

  • DNS Lookup
  • A Lookup
  • AAAA Lookup
  • MX Lookup

Email & Deliverability

  • SPF Lookup
  • DKIM Lookup
  • DMARC Lookup
  • DMARC Generator

Network

  • IP Lookup
  • ASN Lookup
  • Ping
  • Open Port Scanner

SSL / TLS

  • SSL Checker
  • SSL Expiry Checker
  • Certificate Decoder

Domain

  • WHOIS Lookup
  • Domain Age
  • Blacklist Check
  • Domain Health Score

Web

  • HTTP Header Check
  • Security Headers
  • Website Availability
  • Robots.txt Checker

Legal

  • Privacy Policy
  • Terms & Conditions
  • Cookie Policy
  • Disclaimer
  • Acceptable Use
  • GDPR
  • API Terms
  • Responsible Disclosure

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Diagnostics are provided for informational purposes only. See our disclaimer.

Diagnostic tools

Every check in one place. Filter by category or search by name.

Email & Deliverability

SPF Lookup

Fetch and parse a domain's SPF record.

Email & Deliverability

DKIM Lookup

Retrieve a DKIM public key by selector.

Email & Deliverability

DMARC Lookup

Read and interpret a DMARC policy.

Email & Deliverability

DMARC Generator

Build a valid DMARC record interactively.

Email & Deliverability

BIMI Lookup

Check for a BIMI brand logo record.

Email & Deliverability

MX Health

Score mail-server configuration and reachability.

Email & Deliverability

SMTP Test

Connect to a mail server and read its banner.

Email & Deliverability

Email Header Analyzer

Parse raw headers into a delivery timeline.