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Online Network Tools for DNS, IP Addresses, Domains and Connectivity
CyberTools provides a collection of free online network tools for checking IP addresses, DNS records, domains, ports, latency, mail servers, network routes, DNS propagation, blacklist status and website infrastructure.
These browser-based networking utilities are useful for developers, system administrators, website owners, IT professionals and anyone troubleshooting connectivity, domain configuration or server-related problems without installing additional networking software.
Check DNS Records, Mail Servers and Domain Infrastructure
DNS translates domain names into the technical records used by browsers, mail servers and other internet services. When a domain stops resolving correctly, DNS information is one of the first places to investigate.
Use the DNS Lookup to inspect domain records and the MX Lookup to identify mail exchange servers configured for a domain.
The Subdomain Finder can help discover publicly visible subdomains associated with a domain, while the DNS Propagation Check helps verify how DNS changes appear across different resolvers.
Query common DNS records and inspect how a domain is configured.
Identify the mail servers responsible for receiving email for a domain.
Find publicly discoverable subdomains connected with a target domain.
Check whether recently changed DNS records are visible across different locations.
Diagnose Connectivity, Latency and Network Paths
Network problems can occur between your device, DNS infrastructure, hosting provider, routing network or destination server. Several different tests may be needed to isolate the problem.
Start with Ping to measure basic latency, then use Traceroute Online to inspect the network path between systems.
You can also check whether a website responds with the Website Status Checker or test a specific service using the Open Port Checker.
Find IP Information and Convert Between IPs and Hostnames
IP addresses identify network endpoints and are fundamental to internet communication. CyberTools includes several utilities for investigating IP addresses and hostname relationships.
Use What's My IP to view your public-facing IP address or the IP Information Tool to inspect information associated with another IP address.
The Hostname to IP Tool resolves a hostname to an IP address, while IP to Hostname attempts the reverse lookup.
Quickly identify the public IP address visible to internet services.
Investigate available technical and network information associated with an IP address.
Convert hostnames to IP addresses or perform reverse IP-to-hostname lookups.
Calculate network ranges and subnet information using the IP Subnet Calculator.
ASN Lookup and IP Subnet Analysis
Larger networks are commonly organized into Autonomous Systems. The ASN Lookup helps identify information associated with Autonomous System Numbers, including network ownership and assigned IP ranges when available.
Developers and network administrators can also use the IP Subnet Calculator to work with IPv4 and IPv6 network ranges, addressing boundaries and subnet-related calculations.
Analyze Website Technology and Server Configuration
Websites expose useful technical signals through HTTP responses, server headers, DNS information, SSL certificates and application resources.
The Website Technologies Check can help identify technologies, hosting information and other infrastructure indicators associated with a website.
The HTTP Methods Auditor checks which HTTP request methods appear to be enabled by a server. Unexpected methods may deserve further review by the website administrator.
Check IP and Email Blacklist Status
Email delivery and server reputation can be affected when IP addresses, domains or mail infrastructure appear on reputation or anti-spam lists.
Use the IP Blacklist Check to investigate an IP address or domain against supported blacklist sources.
The Email Blacklist Check can help investigate email-related infrastructure and reputation indicators when diagnosing mail delivery problems.
Check for Potential WebRTC IP Leaks
WebRTC enables real-time browser communication, but browser networking behavior may expose IP-related information under certain configurations.
The WebRTC Leak Test helps inspect information exposed through the browser's WebRTC environment so you can better understand your network privacy configuration.
Identify Your Browser User Agent
Browsers send a user-agent string that can contain information about the browser engine, operating system and client environment.
The User Agent Finder displays the user-agent information currently being sent by your browser, which can be useful when debugging compatibility or request behavior.
Useful Networking Utilities for Technical and Everyday Tasks
Which Network Tool Should You Use?
Use CyberTools Network Utilities in Three Steps
Frequently Asked Questions About Network Tools
What are online network tools?
Are CyberTools network tools free?
How can I check DNS records online?
What is DNS propagation?
What does a Ping test measure?
What is Traceroute used for?
What is an open port?
What is an ASN?
Can network tools prove that a server is secure?
Is a blacklist result always proof of spam?
Diagnose Networks Without Installing Extra Software
Choose from DNS, IP, domain, port, routing, blacklist, connectivity and infrastructure tools and run the network check you need directly from your browser.
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