Network Tools — IP, DNS & Security

Network tools are web-based utilities that query, convert, and analyze IP addresses and domain name records without software installation. IP tools query Regional Internet Registries — ARIN, RIPE NCC, APNIC, LACNIC, and AFRINIC — for address ownership and network block data via RDAP (RFC 7480). DNS tools resolve hostnames by querying live resolvers including Google (8.8.8.8) and Cloudflare (1.1.1.1). Security tools perform TLS handshakes (RFC 8446) and detect browser-side exposure. All tools return results in real time.

Most used

IP Blacklist Checker Is my mail server listed? SPF Checker Is my SPF record valid? DNS Lookup What do my DNS records say? Port Checker Is my port open?

IP & Network Tools

IP tools query Regional Internet Registries and DNS resolvers to look up address ownership, geolocation, and blacklist status for any IPv4 or IPv6 address. Converters and calculators handle CIDR notation (RFC 4632), subnet ranges, and address format conversions between decimal, binary, and hex. Diagnostic tools — ping, traceroute, and port checker — test reachability from a neutral external vantage point.

Your connection

What the internet sees when you connect5 tools

What Is My IP Address?

Reveal your public IPv4 and IPv6 address, ISP, ASN, and approximate geolocation — detected automatically on page load.

My Location

Instantly see your IP-based city, country, and ISP — then pinpoint your exact GPS coordinates with one click.

What Is My Internet Service Provider (ISP)?

Detects your Internet Service Provider and Autonomous System Number (ASN) from your current public IP address — results appear on page load.

Proxy Checker

Three checks on your connection: proxy headers, Tor exit list and datacenter / VPN networks.

Internet Speed Test

Measure your broadband download speed, upload speed, ping latency, and jitter from the nearest test server.

Look up an IP or domain

Owner, network, location and reputation of any address8 tools

IP Lookup

Returns country, city, region, ISP, ASN, hostname, and coordinates for any IPv4 or IPv6 address.

IP Whois Lookup

Find the registered owner, network block, CIDR range, country, and abuse contact for any IPv4 or IPv6 address.

IP Blacklist Checker

Check any IPv4 or IPv6 address against 18 public DNS-based blocklists for spam, botnet, and abuse listings.

IP to ASN Lookup

Find the Autonomous System Number (ASN) and registered network operator for any IPv4 or IPv6 address.

ASN WHOIS Lookup

Retrieve the registered owner, network name, org handle, and address for any Autonomous System Number via live RDAP and WHOIS data.

Domain to IP

Find the IPv4 and IPv6 addresses of any website or domain via live DNS resolution.

IP to Domain / Reverse IP Lookup

Perform a PTR record lookup to find the hostname registered to any IPv4 or IPv6 address — used to verify reverse DNS configuration for mail servers.

Domain WHOIS Lookup

Look up the registered owner, registrar, nameservers, and expiry date for any domain name.

Test reachability

From our server to your host4 tools

Ping

Send 5 ICMP echo requests to any IPv4 address, IPv6 address, or hostname and see real-time RTT, packet loss, and latency statistics.

Traceroute

Trace the network path to any IPv4 address, IPv6 address, or hostname — hop by hop, streamed live.

Port Checker

Tests whether a specific TCP port on any hostname or IP address is open and accepting connections from the public internet.

Website IPV6 Support Test

Queries AAAA DNS records from authoritative name servers to verify whether a website or domain is reachable over IPv6.

Subnets & CIDR

Plan and check address ranges4 tools

IP Subnet Calculator & Visualizer / CIDR Calculator

Interactive CIDR tool with live binary bit-mapping — calculates network address, broadcast, host range, usable hosts, and subnet mask for any IPv4 prefix.

IPv6 Subnet Calculator & Planner

128-bit prefix planning with RFC 5952 canonical compression — calculates network prefix, total address count, and range boundaries for any IPv6 prefix length.

IP Range to CIDR Converter (IPv4/IPv6)

Convert a start and end IP address into the minimal set of CIDR blocks for any IPv4 or IPv6 range.

Is IP Address In CIDR Range?

Enter any IPv4 or IPv6 address and a CIDR block to check whether the IP belongs to the subnet — result is instant.

Convert & format

Change how an address is written7 tools

IPv4 to IPv6

Get the IPv4-mapped IPv6 representation for any IPv4 address — ::ffff: notation per RFC 4291, single or bulk mode.

IPv6 to IPv4

Extract the embedded IPv4 address from any IPv4-mapped IPv6 (::ffff:) address — hex or dotted-decimal notation, single or bulk.

IP to Decimal

Convert any IPv4 or IPv6 address to its 32-bit or 128-bit decimal integer representation — single address or bulk list with copy-all output.

IP to Binary

Convert any IPv4 address to four 8-bit binary octets or any IPv6 address to sixteen 8-bit groups — used for subnet mask and routing analysis.

IP to Hex

Convert any IPv4 or IPv6 address to its hexadecimal representation — the format used in network protocol headers and hardware configuration.

IPv6 Compression Tool

Shorten any full IPv6 address to its RFC 5952 canonical form — leading zeros removed, longest zero run replaced with ::. Single address or bulk list.

IPv6 Expand Tool

Expands any compressed IPv6 address to the full RFC 4291 §2.2 notation — eight groups of four lowercase hex digits, all leading zeros restored.

Check & clean lists

Validate, classify, extract, sort6 tools

IP Validator

Validate IPv4 and IPv6 addresses for syntax, version, and address class — single address or bulk list with Copy Valid filter.

Is This a Public or Private IP?

Determine whether an IPv4 or IPv6 address is publicly routable or falls within a private range — RFC 1918 for IPv4, RFC 4193 for IPv6 ULAs.

IP Class Checker

Identify the classful network class (A, B, C, D, or E) and default subnet mask for any IPv4 address per the original RFC 791 addressing scheme.

IP Extractor

Scans any block of text or log output and extracts all valid IPv4 and IPv6 addresses — useful for parsing server logs, email headers, and firewall rule sets.

IP Sorter

Sort a list of IPv4 or IPv6 addresses numerically in ascending or descending order — paste a list, select order, copy or download the sorted result.

Random IP Generator

Generate random public IPv4 or IPv6 addresses for firewall rule testing, network simulation, and configuration validation — bulk output supported.

DNS Tools

DNS tools query live resolvers — Google (8.8.8.8), Cloudflare (1.1.1.1), Quad9 (9.9.9.9), and authoritative name servers — to retrieve A, AAAA, MX, NS, CNAME, SPF, and TXT records for any domain. Time-to-live (TTL) values are returned with each record. Results reflect the current live state of the DNS per RFC 1034 and RFC 1035 — not a cached snapshot.

Look up a domain

Records that point a name to its servers5 tools

DNS Lookup

View all DNS records for any domain — A, AAAA, MX, NS, TXT, CNAME, SRV, SPF — from Google, Cloudflare, Quad9, OpenDNS, or authoritative DNS.

Website to IP Lookup

Find the IPv4 and IPv6 addresses of any website or domain via live DNS resolution.

Reverse DNS Lookup

Perform a PTR record lookup to find the hostname registered to any IPv4 or IPv6 address — used to verify reverse DNS configuration for mail servers.

CNAME Lookup

Returns the canonical alias target and TTL (seconds) for any domain or subdomain, via Google, Cloudflare, Quad9, OpenDNS, or authoritative name servers.

NS Lookup (Name Servers)

Find the authoritative nameservers for any domain — returned with nameserver hostname and TTL in seconds.

Email records

Records that decide where mail goes and who may send it3 tools

MX Lookup

Find the mail servers handling email for any domain — server hostnames, priority order, and TTL in real time.

SPF Lookup

Find the Sender Policy Framework record for any domain — see authorized mail servers, mechanisms, and sending policy.

TXT Lookup

View all TXT records for any domain — SPF, DKIM, DMARC, and domain verification tokens — from 5 resolvers or authoritative DNS.

Security & Privacy Tools

Security tools perform live TLS handshakes (RFC 8446) to inspect SSL/TLS certificates, retrieve HTTP response headers including HSTS (RFC 6797) and Content-Security-Policy, and test HTTP/2 support (RFC 7540). Browser-side privacy tools detect WebRTC IP leaks (RFC 5389), generate browser fingerprint profiles, and check for the Global Privacy Control signal (W3C GPC specification).

Test your browser

What your browser reveals about you3 tools

Browser Fingerprint Test

Detects screen resolution, user agent, browser engine, and system timezone — the four signals used to generate your unique fingerprint hash.

WebRTC Leak Test

Compares the IP websites see with the public and local addresses your browser reveals through WebRTC. Same IP: no leak.

Global Privacy Control (GPC) Test

Detects whether your browser is actively sending Sec-GPC: 1 — the Do Not Sell opt-out signal required under CCPA and US state privacy laws.

Check a website

Certificate, headers and protocol support5 tools

SSL Certificate Checker

Checks expiry date, issuer, trust chain depth, and HSTS status for any domain's SSL/TLS certificate via a live TLS handshake on port 443.

HTTP Header Checker

Fetches all HTTP response headers from any domain — status code, server software, cache-control, and security headers including HSTS and Content-Security-Policy.

HTTP2 Support Test

Negotiates an ALPN extension (RFC 7301) during the TLS handshake to detect whether the target server advertises HTTP/2 (h2) support — the binary, multiplexed successor to HTTP/1.1.

Brotli Compression Test

Sends an Accept-Encoding: br request header and verifies whether the server responds with Content-Encoding: br — Google's Brotli algorithm, reducing payload sizes 15–25% versus gzip.

Secure Cookie Checker

Parses Set-Cookie response headers from any domain to show the Secure, HttpOnly, and SameSite security attributes on each cookie.

Email security

Trace where a message really came from1 tools

Email Header Analyzer

Parses raw email headers to reconstruct the delivery path, extract the originating IP, and show the SPF, DKIM, and DMARC results recorded in the headers.

Common Network Investigation Workflows

Network tools work best in sequence: the result of each step feeds the next one. Pick the question you want to answer and follow its line.

IP Investigation

Who is behind an IP address? 6 steps

What Is My IPfind your own public IP address
IP Geolocationcountry, city, ISP and ASN
IP WHOISregistered owner and network block (RDAP, RFC 7480)
IP to ASNthe Autonomous System and its operator
Reverse DNSthe PTR hostname of the IP
IP Blacklistlistings on 18 spam and abuse blocklists

Email Deliverability

Why is my email going to spam? 5 steps

MX Lookupthe mail servers that receive email for the domain
Reverse DNSthe PTR hostname of the mail server IP; it should point back to the same IP (FCrDNS)
IP Blacklistis the mail server IP on a spam blocklist?
SPF Lookupwhich servers may send email for the domain
TXT LookupDMARC and DKIM records, e.g. _dmarc.example.com

Domain Investigation

Who runs this website? 5 steps

Website to IPthe domain’s IPv4 and IPv6 addresses
IP Geolocationhosting region, ISP and network of that IP
IP WHOISthe organization that owns the IP block
Domain WHOISregistrar, registration and expiry dates
SSL Certificatecertificate issuer, expiry date and chain

Network Diagnostics

Why can’t I reach my server? 5 steps

Pingis the host reachable, and how fast?
Port Checkeris the TCP port open, closed or filtered?
Traceroutethe hop-by-hop path to the target
DNS Lookupdoes the domain resolve correctly?
Reverse DNSis a PTR record set for the server IP?

Frequently Asked Questions

What are network tools?

Network tools are web-based utilities that query, convert, and analyze IP addresses and domain name records without software installation. IP tools query Regional Internet Registries — ARIN, RIPE NCC, APNIC, LACNIC, and AFRINIC — for address ownership and network block data via RDAP (RFC 7480). DNS tools query live resolvers for hostname records. Security tools perform TLS handshakes (RFC 8446) and detect browser-side exposure. All tools return results in real time.

How accurate are the results from network tools?

Accuracy varies by tool type. WHOIS and RDAP data is sourced directly from the five Regional Internet Registries and reflects the current registered state. DNS results are returned live from the resolver selected. IP geolocation is accurate to country level in approximately 99% of cases and to city level in approximately 81% of cases — street-level precision is not possible from IP data alone.

Why does a network tool return no result?

No-result responses have specific causes per tool. WHOIS queries return no result for private IP ranges defined in RFC 1918, such as 192.168.x.x or 10.x.x.x, which have no registry record. DNS tools return no result when the queried record type does not exist for the domain. Reverse DNS returns empty when no PTR record is configured — common for cloud provider IP blocks. Port checks return closed when a firewall blocks the connection before it reaches the target port.

What is the difference between IP tools and DNS tools?

IP tools operate on Internet Protocol addresses — performing lookup, conversion, validation, and diagnostic operations on IPv4 and IPv6 addresses directly. DNS tools operate on the Domain Name System — resolving hostnames to IP addresses and querying record types including A, AAAA, MX, NS, CNAME, SPF, and TXT. The two systems are interconnected: a domain name resolves to an IP address via DNS, and that IP address has registration records accessible via RDAP and WHOIS.

Do you store or log the IP addresses and domains queried?

No. Results are processed in real time and returned directly to your browser. IP addresses and domain names submitted to any tool on this site are not stored, logged, or shared with third parties. DNS queries are forwarded to the resolver you select — Google (8.8.8.8), Cloudflare (1.1.1.1), or Quad9 (9.9.9.9) — and are subject to those resolvers' own privacy policies.