Free IP & Network Tools
Subnet calculator, DNS lookup, WHOIS, SSL checker, and more — all free, fast, and private. No signup required.
Which IP Tools Are Available?
Convert, calculate, and analyze IP addresses and network ranges. From subnet calculations to IPv6 expansion, these tools handle the math so you don't have to.
Subnet Calculator
Calculate network address, broadcast, host range, and more from any IP and CIDR. Essential for firewall and network security planning.
Open toolIP Address Converter
Convert IP addresses between decimal, binary, hexadecimal, and octal formats.
Open toolASN Lookup
Look up Autonomous System Number details — identify the organization, network reputation, and allocated IP ranges.
Open toolVisual Traceroute
Trace the network path to any IP or hostname. Visualize each hop on a map to identify routing issues or suspicious intermediaries.
Open toolIP Compare
Compare two IP addresses side by side — location, network, distance, and more on a map.
Open toolWhat Is My Timezone
Detect your current timezone, UTC offset, and local time instantly from your browser.
Open toolCIDR to IP Range Converter
Convert CIDR notation to IP address ranges — see first IP, last IP, subnet mask, and total hosts. Useful for firewall rule planning.
Open toolIPv6 Expander / Compressor
Expand compressed IPv6 addresses to full form or compress expanded ones to shorthand notation.
Open toolIP Range to CIDR Converter
Convert an IP address range to the smallest set of CIDR blocks that cover it exactly.
Open toolMAC Address Lookup
Look up the manufacturer of any network device by its MAC address using the IEEE OUI database.
Open toolWhat DNS & Domain Tools Can You Use?
Query DNS records, resolve hostnames, look up domain registration details, and identify network device manufacturers using authoritative data sources.
Reverse DNS Lookup
Find the hostname associated with any IP address via PTR record lookup. Verify server identity and detect suspicious hosts.
Open toolDNS Lookup
Query DNS records for any domain — A, AAAA, MX, NS, TXT, CNAME, SOA, and more. Verify email authentication and domain configuration.
Open toolWHOIS Lookup
Query WHOIS records for any domain — registrar, creation date, expiry, nameservers, and domain ownership details.
Open toolWhat Security Analysis Tools Are Included?
Inspect HTTP headers, validate SSL certificates, check IP reputation against blacklists, test open ports, and analyze email headers for security auditing.
What Is My User Agent
See what your browser reveals — user agent string, browser version, OS, and device details that websites can see.
Open toolEmail Header Analyzer
Trace email delivery paths, detect spoofing attempts, and inspect SPF/DKIM/DMARC authentication from raw headers.
Open toolHTTP Header Checker
Audit HTTP security headers for any URL — check CSP, HSTS, X-Frame-Options, and get a security grade (A-F).
Open toolSSL Certificate Checker
Validate SSL/TLS certificates — detect expired, misconfigured, or expiring certificates. Check issuer, chain, and protocol.
Open toolIP Blacklist Check
Scan any IP against 12 major spam and security blacklists — Spamhaus, Barracuda, SpamCop, and more. Check your email reputation.
Open toolPort Checker
Scan for open ports on any IP or hostname — verify firewall rules, check service availability, and assess attack surface.
Open toolIP Reputation Check
Check any IP address for threats, VPN/proxy usage, blacklist presence, and risk score. Instant security verdict.
Open toolVPN & Proxy Detector
Detect if an IP address is using a VPN, proxy, Tor, relay, or hosting provider. Identify anonymous connections.
Open toolIP Abuse Report Checker
Check if an IP is listed on abuse blacklists. View abuse contact, threat indicators, and network reputation.
Open toolSecurity Header Scanner
Scan any website for security headers. Get a security grade, detailed findings, and actionable recommendations.
Open toolWhat Are IP & Network Tools?
IP and network tools are utilities that help you inspect, troubleshoot, and manage internet infrastructure. They query real-time data from DNS servers, WHOIS registrars, IP geolocation databases, and threat intelligence feeds to give you accurate information about domains, IP addresses, and network configurations. These browser-based tools replace command-line utilities like nslookup, dig, and whois with visual interfaces that work on any device.
Who Are These Tools For?
These tools are built for anyone who works with IP addresses and networks. System administrators use them to troubleshoot connectivity issues, verify DNS propagation, and audit server configurations. Security professionals check IP reputation, inspect HTTP headers, and validate SSL certificates during penetration testing and incident response.
Developers use subnet calculators and CIDR converters when designing network architectures or configuring cloud infrastructure. Non-technical users can check their own IP address, verify their VPN is working, or look up who owns an IP address — all without needing to install software or understand command-line tools.
How Do Online Network Tools Work?
Each tool queries authoritative data sources in real time. DNS Lookup sends queries to nameservers and returns the actual records (A, AAAA, MX, CNAME, TXT). WHOIS Lookup retrieves registration data directly from domain registrars. Reverse DNS resolves IP addresses back to hostnames by querying PTR records.
IP-focused tools like the Subnet Calculator and CIDR to IP Range converter perform calculations locally in your browser — your data never leaves your device. Security tools like IP Blacklist Check query multiple threat databases simultaneously to check if an IP appears on spam or abuse lists.
Browser-Based vs Desktop Network Tools
Traditional network tools like nslookup, tracert, and whois require a terminal and are limited to the operating system they run on. Browser-based tools offer the same functionality with a visual interface, work on any device (including phones and tablets), and often provide additional context like geolocation data or threat intelligence.
For example, our Visual Traceroute maps each network hop on a world map, while the command-line traceroute only shows IP addresses and latency numbers. Our Email Header Analyzer parses complex email headers into a readable timeline, a task that would take significant manual effort otherwise.
Where Does the Data Come From?
Our tools query authoritative sources including MaxMind GeoLite2 and DB-IP for IP geolocation, the IEEE OUI database for MAC address lookups, IANA registries for port and protocol data, and real-time DNS and WHOIS servers for domain information. We cross-reference multiple databases to improve accuracy. For full details, see our Data Sources page.