2network — Free Network Tools for IT Professionals

2network is a free, privacy-first collection of 16 professional network tools that run entirely in your browser. Subnet calculators, DNS lookups, SPF/DMARC/DKIM builders, a port reference with vulnerability data, TLS diagnostics, IP geolocation — no sign-up, no tracking, no data retention.

Open Port Lookup →

What Is 2network?

2network is a web-based network tools platform built for IT professionals, sysadmins, network engineers, and developers who need quick, accurate answers without installing software or signing up for accounts. Every tool is free, every request is anonymized, and the 2network core tools run entirely client-side so your queries never leave your browser. The handful of tools that must hit a remote server (DNS-over-HTTPS, TLS inspection, IP geolocation, Whois) are proxied through stateless Netlify Functions that keep no logs.

The goal is simple: deliver the 20% of network tools you reach for 80% of the time, polished, fast, and respectful of your privacy.

Which Network Tools Does 2network Include?

2network ships with 16 tools organized into four categories. Here is the full list:

Ports & Protocols

  • Port Lookup — Search 110+ TCP/UDP ports with service names, protocol details, known vulnerabilities sourced from NIST NVD, and ready-to-paste Wireshark display filters.

IP & Subnet Tools

  • IPv4 Subnet Calculator — Network address, broadcast, host range, wildcard mask, and host count from any IP/CIDR input.
  • VLSM Calculator — Variable-length subnet mask designer for carving a supernet into multiple variable-size subnets.
  • Wildcard Mask Calculator — Convert subnet masks to wildcard masks for ACLs.
  • IP Address Converter — Convert between dotted-decimal, binary, hexadecimal, and integer IP representations.
  • IPv6 Tools — Expand, compress, and generate EUI-64 addresses for IPv6 networks.

DNS & Email Authentication

  • DNS Lookup — Query A, AAAA, MX, TXT, CNAME, NS, SOA, and more via DNS-over-HTTPS against Google, Cloudflare, or Quad9.
  • SPF Record Builder — Visual editor for Sender Policy Framework records with include/ip4/ip6/mx/a mechanisms.
  • DMARC Record Builder — Step-by-step DMARC policy generator (none/quarantine/reject) with aggregate and forensic report addresses.
  • DKIM Record Generator — Generate DKIM key pairs and TXT record values.
  • Reverse DNS Tool — PTR record lookups for IPv4 and IPv6.
  • DNS Record Generator — Format valid A, AAAA, CNAME, MX, and TXT records from form input.

Diagnostics

  • HTTP Header Analyzer — Inspect response headers, status, redirects, security headers, and caching directives for any URL.
  • TLS / SSL Checker — Certificate chain, protocol versions, cipher suites, and security header audit.
  • Whois / RDAP Lookup — Domain and IP ownership data sourced from RDAP registries.
  • IP Geolocation — Country, city, ISP, and ASN mapping for any IPv4 or IPv6 address.

Who Is 2network For?

  • Network engineers designing subnets, debugging routing, or validating firewall rules.
  • System administrators troubleshooting DNS propagation, email authentication, and TLS certificates.
  • Security professionals investigating ports, vulnerabilities, and IP reputation.
  • Developers and DevOps engineers configuring HTTP headers, DNS records, and cloud networking.
  • Students and instructors learning networking fundamentals with instant visual feedback.
  • MSPs and IT consultants who need quick, trustworthy answers during client calls.

How Does 2network Protect Your Privacy?

2network is built on a zero-data-retention policy. No queries are logged, no IP addresses are stored in plaintext, and no accounts or cookies are required. Client-side tools like the subnet calculator, IP converter, IPv6 tools, wildcard mask, VLSM, SPF/DMARC/DKIM builders, and record generators never send data anywhere at all.

The remote tools (DNS lookup, TLS check, HTTP headers, Whois, IP geolocation) route through Netlify Functions that proxy to public APIs without logging the query. The only data retained is aggregate, anonymized page-view analytics with SHA-256 hashed session identifiers.

What Is a Subnet Calculator?

A subnet calculator is a tool that derives network details from an IP address and CIDR prefix. Given an input like 192.168.1.0/24, it returns the network address, broadcast address, the range of usable host addresses, the subnet mask in dotted-decimal and binary, the wildcard mask used in ACLs, and the total number of available hosts. Subnet calculators are essential for network design, VLAN planning, firewall rule writing, and troubleshooting routing issues.

What Is a DNS Lookup?

A DNS lookup is a query that resolves a domain name into a specific record type — an IPv4 address (A record), an IPv6 address (AAAA record), a mail server (MX record), a text record (TXT), or a name server (NS), among others. 2network's DNS lookup uses DNS-over-HTTPS (DoH) so queries are encrypted in transit and can be directed to Google, Cloudflare, or Quad9 resolvers to compare answers.

What Are SPF, DKIM, and DMARC?

SPF, DKIM, and DMARC are the three DNS-based email authentication standards that protect your domain from spoofing and phishing. SPF (Sender Policy Framework) lists the IP addresses authorized to send mail for your domain. DKIM (DomainKeys Identified Mail) cryptographically signs outgoing messages so the receiver can verify they were not tampered with. DMARC (Domain-based Message Authentication, Reporting & Conformance) ties SPF and DKIM together with a policy that tells receiving servers what to do when a message fails authentication — nothing, quarantine, or reject.

2network includes visual builders for all three records so you can compose them correctly on the first try.

Frequently Asked Questions

Is 2network free to use?

Yes. Every tool on 2network is free, with no sign-up, no paywall, no usage limits, and no ads. It is funded as an open resource by the 2suite ecosystem.

Does 2network store my queries or IP address?

No. 2network runs client-side wherever possible, and the few tools that need a server proxy through stateless Netlify Functions that do not log query data. IPs are SHA-256 hashed before anonymous page-view analytics are recorded.

Does 2network work offline?

The calculator-style tools (subnet, VLSM, wildcard, IP converter, IPv6, SPF/DMARC/DKIM/record builders) work entirely in your browser and will run offline once the page has loaded. The diagnostic tools (DNS, TLS, HTTP headers, Whois, geolocation) need an active internet connection to reach their upstream services.

How accurate are the results?

Port and vulnerability data comes from IANA and the NIST National Vulnerability Database. DNS lookups use production DoH endpoints. Subnet math is validated against reference calculators. If you spot anything wrong, the feedback widget at the bottom of every page goes straight to the maintainer.

Can I use 2network for commercial or professional work?

Yes. 2network is designed for IT professionals, consultants, MSPs, and in-house network teams. Use it for troubleshooting, audits, documentation, and client work. There are no licensing restrictions on the free tools.

What makes 2network different from other network tool sites?

Three things: it is completely free with no sign-up, it respects your privacy with a zero-retention policy, and it bundles 16 professional-grade tools in one place with a consistent, fast, modern interface. Most comparable sites are either paywalled, ad-laden, or scattered across multiple domains.

Explore the 2suite Ecosystem

2network is part of a growing family of free, privacy-first web tools:

  • 2seo — Free unlimited SEO and AI readiness analysis.
  • 2prompt — Master prompt wizard for Claude, ChatGPT, and Gemini.
  • 2redact — Client-side document redaction for PDFs, images, and spreadsheets.
  • 2count — Zero-friction character and word counter for writers.
  • 2convert — Universal file converter that runs in your browser.