Network Tools

Analyze IP addresses with CIDR calculator, subnet mask, network range, and format converter for decimal, binary, and hex

IPv4 subnet calculator with CIDR support — compute network address, broadcast, mask, and host range instantly, right in your browser.

Generate and validate MAC addresses

Look up the vendor/manufacturer (OUI) of any MAC address from a bundled offline IEEE dataset - unicast/multicast detection, format conversion, and EUI-64 derivation, fully in-browser

Perform DNS lookups and view DNS records

View and analyze HTTP headers

Calculate IP ranges and subnet information

Scan ports to check for open connections

Lookup domain registration information

Build and validate SPF DNS TXT records

Build and validate DMARC DNS TXT records

Expand compressed IPv6 addresses to full form and compress them back to canonical notation, with validation and a per-group breakdown.

Build and validate DKIM DNS TXT records from a public key

Build and validate DNS CAA records (RFC 8659)

Build a BIMI DNS TXT record (v=BIMI1) from your SVG logo URL and optional Verified Mark Certificate URL, and publish it at default._bimi.yourdomain.com.

Generate MTA-STS DNS TXT records and HTTPS policy files for STARTTLS enforcement

Generate RFC 4193 IPv6 Unique Local Addresses (fd00::/8) from a MAC address and timestamp via SHA-1, with /48 prefix, first and last host, and reproducible seeding - entirely in your browser.

Measure download, upload, latency, and jitter in your browser using same-domain assets - no third-party API, no ads.

Browse RFC 2132 DHCP options and build custom option 43/60/66 hex payloads for VoIP phones and routers.

Look up well-known TCP and UDP ports by number or service name with protocol, description and common-risk flags from a bundled IANA-based dataset of 60+ ports. Fully offline in your browser.

Compose nmap scan commands from visual pickers of target, scan type, ports, timing template and verbosity, with plain-English explanations for every flag and copy-paste output, for authorized network reconnaissance.

Compute optimal TCP MSS from MTU across Ethernet, PPPoE, GRE, VXLAN, OpenVPN, WireGuard and IPsec tunnels, with per-encapsulation overhead chart, fragmentation-avoidance guidance and a ping -M do path-MTU probe command.