IPv4 Subnet Calculator
Free IPv4 CIDR subnet calculator: instantly compute network address, subnet mask, broadcast IP, wildcard mask, usable host range, and total hosts.
Interactive Networking Calculators & Checklists
Fast, privacy-friendly utilities that run 100% locally in your browser—no signups, no cloud tracking, and instant reference tables.
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WiFi Channel Planner
Free interactive WiFi channel planner for 2.4 GHz, 5 GHz (UNII-1, DFS, UNII-3), and 6 GHz bands. Find non-overlapping channels and optimal channel widths.
Router Default Login Finder
Look up the default gateway IP address, admin login URL, default username/password policy, and support page for all 16 major router and switch brands.
Router Security Checklist Generator
Generate a customized router and WiFi security hardening checklist for your home or small office: WPA3, WPS, UPnP, admin access, DNS, and IoT VLANs.
Internet Speed Troubleshooting Checklist
Diagnose slow internet speeds, high ping, packet loss, and 100 Mbps bottlenecks step-by-step across your ISP modem, Ethernet cabling, router QoS, and WiFi.
Ethernet Cable Selector Tool
Choose the right Ethernet cable category (Cat5e, Cat6, Cat6a, or OS2/OM4 Fiber) and jacket rating (CMR, CMP, Direct Burial) for 1G, 2.5G, and 10G runs.
VPN Router Compatibility & Speed Estimator
Estimate WireGuard vs OpenVPN router speeds based on CPU architecture and firmware, and check if your router supports VPN client and split tunneling.
PoE Switch Wattage & Budget Calculator
Calculate total IEEE 802.3af/at/bt PoE switch wattage for IP cameras, WiFi 6E/7 access points, and VoIP phones with a 20% power safety margin.
Router & Modem UPS Runtime Calculator
Calculate how many hours a 450VA to 1500VA UPS battery backup will run your fiber ONT, cable modem, WiFi router, PoE switch, and NAS during outages.
WireGuard Config & AllowedIPs Generator
Generate client and server WireGuard .conf templates, calculate split-tunnel AllowedIPs CIDR blocks, and compute optimal MTU for fiber or PPPoE.
IPv6 Prefix Delegation (/56 & /60) Calculator
Split an ISP-assigned /56 or /60 IPv6 Prefix Delegation block into clean /64 SLAAC VLAN subnets for Main LAN, Guest WiFi, IoT, and Work networks.
NVR Storage & 4K Camera Bitrate Calculator
Calculate how many terabytes your NVR needs for 24/7 security cameras. Enter camera count, resolution (1080p to 4K), codec (H.265 vs H.264), and retention days.
Wi-Fi Link Budget & Path Loss Calculator
Free Wi-Fi link budget and free-space path loss (FSPL) calculator. Compute RSSI, fade margin, obstacle loss, and modulation speeds across 2.4, 5, and 6 GHz.
Server Rack Unit (U) & Thermal BTU Sizing Calculator
Calculate equipment rack unit space (U), continuous electrical wattage, BTU/hr heat dissipation, and required ventilation airflow (CFM) for server racks.
PoE Cable Distance & Voltage Drop Calculator
Calculate Ethernet PoE cable voltage drop, wattage loss, and maximum distance for 802.3af, 802.3at PoE+, and 802.3bt across 23 AWG Cat6 and 24 AWG Cat5e.
MTU & TCP MSS Clamping Calculator
Calculate exact Path MTU, PPPoE/WireGuard/OpenVPN/IPsec TCP MSS clamp values, and Windows/Linux/macOS DF ping probe sizes to stop packet fragmentation.
Interactive Firmware Update Checklist
Pre-flight verification checklist and rollback guide before flashing any router, switch, or access point firmware.