Free IP, DNS & Network Tools
Look up DNS records, check your IP, calculate subnets, inspect HTTP headers, and more. No signup, and the addresses you look up are never stored or sent to analytics — most calculations run right in your browser.
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See your public IPv4/IPv6 address, network, and connection details.
Look up any IP: version, type, network, registry data, and reverse DNS.
Query A, AAAA, MX, TXT, NS, CNAME, SOA, CAA, SRV and PTR records.
Compare DNS answers across multiple public resolvers to spot inconsistencies.
Calculate network, broadcast, masks, ranges and host counts for IPv4/IPv6.
Validate and classify single or bulk IPv4/IPv6 addresses — no network calls.
Structured registration data for domains, IPs and ASNs via RDAP.
Check MX, SPF, DMARC and DKIM records and get a mail-DNS health summary.
Inspect response status, redirect chain and HTTP headers for any public URL.
Review CSP, HSTS, and other HTTP security headers for a public URL.
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Only tool names are remembered in this browser — never the addresses or domains you entered.
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IP Tools
Look up, validate, convert, and inspect IPv4 and IPv6 addresses.
DNS Tools
Query DNS records and compare answers across public resolvers.
DNS Record Types
Look up one record type at a time — A, AAAA, MX, TXT, NS, CNAME, SOA, CAA or SRV — with an explanation of every field.
Domain Tools
RDAP/WHOIS registration data and domain ownership diagnostics.
Email DNS Tools
Check MX, SPF, DMARC and DKIM records for a mail domain.
Website Diagnostics
Inspect HTTP responses, redirect chains, headers, and response time.
Security Tools
Review HTTP security headers and transport-security configuration.
Network Calculators
Subnet, CIDR, and address conversion — computed in your browser.
Why this site
Built for quick, honest diagnostics
- Fast results
Queries run at the edge and calculators run locally — no waiting on page reloads.
- No installation
Everything works in the browser. No CLI, no account, no signup wall.
- Privacy focused
The addresses, domains and URLs you look up are never stored, never shared-cached, and never sent to analytics.
- Mobile friendly
Long IPv6, TXT and header values stay readable on a phone instead of breaking the layout.
- Readable diagnostics
Every result explains what it means, not just what the resolver returned.