The complete diagnostic platform for engineers who ship
Run DNS, MX, SPF, DMARC, DKIM, SSL, WHOIS, blacklist and network diagnostics in one premium toolkit built for engineers.
Popular tools
The checks engineers reach for every day.
DNS Lookup
Query any DNS record type for a domain.
MX Lookup
List mail exchangers and their priorities.
PTR / Reverse DNS
Resolve an IP address back to a hostname.
SPF Lookup
Fetch and parse a domain's SPF record.
DMARC Lookup
Read and interpret a DMARC policy.
MX Health
Score mail-server configuration and reachability.
IP Lookup
Geolocation, ASN and network owner for an IP.
SSL Checker
Validate a site's certificate and chain.
WHOIS Lookup
Registration, registrar and nameserver details.
Blacklist Check
Test an IP or domain against DNSBLs.
Domain Health Score
Aggregate DNS, email and SSL into one score.
HTTP Header Check
Inspect response headers for a URL.
Hash Generator
Compute MD5, SHA-1 and SHA-256 digests.
Subnet Calculator
Compute network, broadcast and host ranges.
Explore by category
DNS
Resolve and audit every DNS record type.
Email & Deliverability
SPF, DKIM, DMARC, SMTP and mail-flow diagnostics.
Network
Ping, ports, reverse DNS, ASN and IP intelligence.
SSL / TLS
Certificate, chain and HTTPS validation.
Domain
WHOIS, age, blacklist and reputation checks.
Web
Headers, availability and security posture.
Developer Utilities
Encoders, hashing, calculators and converters.
Why NetInsight
Instant, live results
Every check queries authoritative sources in real time — no cached guesses.
Actionable guidance
Results come with severity indicators and concrete remediation steps, not just raw records.
Privacy-first
Client-side utilities never leave your browser; server checks are rate-limited and never sold.
Built for speed
A modern Next.js stack tuned for Core Web Vitals and accessibility.
Trusted by practitioners
“The mail-flow and DMARC breakdown saved me an afternoon of manual digging.”
“Clean API endpoints meant I wired these checks straight into our monitoring.”
“Finally a diagnostics suite that looks as good as it works. Clients love the reports.”
Frequently asked questions
What is NetInsight Toolkit?+
A unified platform for DNS, email deliverability, SSL, WHOIS, network and web diagnostics — designed for engineers who need answers fast.
Do I need an account?+
No. Every core tool works instantly without signup. An optional dashboard adds saved domains, history and monitoring.
Are the tools really live?+
Yes. Server-side tools query real resolvers, mail servers and certificate endpoints; browser utilities compute locally.
Is there an API?+
Every server-side tool exposes a JSON endpoint at /api/tools/{slug}. See any tool page for a ready-to-run cURL example.
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