KalkuNet — Network, Server, Linux & CCTV Engineering Calculators
Instant in-browser computational tools for Network Engineers, Sysadmins, DevOps, and CCTV Integrators. Zero login, zero server-side data dispatch.
🔥Most Popular Engineering Calculators
Instant access to the 4 most-used calculators every day
IPv4 Subnet & CIDR Calculator
Compute Netmask, Network ID, Broadcast, Usable Host Range and Wildcard Mask.
VLSM & Subnet Splitter
Divide multi-department IP blocks efficiently without wasting host addresses.
MikroTik PCC Load Balance Generator
Automated multi-WAN PCC mangle scripts, check-gateway failover & NAT routing.
CCTV Storage & Bitrate Calculator
Estimate NVR/DVR HDD capacity based on H.264/H.265 codecs and retention days.
Directory of 47 Tools
Showing 47 of 47 calculatorsIPv4 Subnet and CIDR Calculator
Calculate IPv4 network address, broadcast, usable host range, netmask, wildcard, binary mask, and RFC address type (RFC 1918, /31, CGNAT).
IPv4 Subnet Split and VLSM Planner
Split an IPv4 network into N equal subnets or allocate boundary-aligned VLSM blocks by required host count with CSV and Markdown export.
IPv6 Subnet Calculator and Prefix Planner (/48, /56, /64)
Expand and compress IPv6 addresses per RFC 5952, calculate network prefix boundaries, /64 SLAAC subnet counts, and child prefix blocks.
MikroTik Bandwidth Calculator (Simple Queue, Burst, PCQ, FQ-CoDel)
Calculate Limit-At (CIR), Max-Limit (MIR), Burst, PCQ, and FQ-CoDel for RouterOS v7 with automated configuration script generation.
MikroTik Multi-WAN PCC Load Balance Calculator
Multi-WAN (2–5 ISP) proportional PCC load balancing and recursive failover configuration script generator for RouterOS v7.
MikroTik Port Forwarding (DST-NAT) and Hairpin NAT Generator
Expose internal server/NVR ports to the public internet (DST-NAT) and eliminate local loopback timeouts using Hairpin NAT.
MikroTik QoS Priority and Anti-Lag Calculator
Prioritize WhatsApp calls, Zoom/Teams conferences, and gaming latency above bulk downloads using RouterOS v7 FQ-CoDel Queue Trees.
MTU and TCP MSS Clamping Calculator
Calculate optimal MTU sizes, TCP MSS clamping (IPv4/IPv6), and Don't Fragment ping payloads to resolve web page freezes over PPPoE and VPN tunnels.
MikroTik WireGuard VPN MTU & MSS Calculator
Deploy site-to-site WireGuard VPN on RouterOS v7 with automatic TCP MSS Clamping to prevent tunnel web page freezes and PMTUD black holes.
Proxmox ZFS & Hardware RAID Capacity Calculator
Calculate net usable Proxmox VE ZFS capacity, padding loss, slop space, 80% safe ceiling, ARC RAM, and zpool create CLI script.
RAID 0/1/5/6/10 Capacity Calculator
Calculate usable storage, parity loss, disk efficiency, and fault tolerance across RAID 0, 1, 5, 6, 10, 50, and 60 configurations.
Server UPS VA/kVA & Battery Runtime Calculator
Calculate server UPS capacity (kVA/VA), VRLA battery runtime (Ah), and 24/7 monthly electricity cost with 25% safety margin and power factor.
Server Room Cooling (BTU/hr & PK) & Rack Unit Calculator
Calculate server room heat dissipation in BTU/hr, convert to air conditioning PK ratings with 24/7 redundancy, and size server racks with airflow buffer.
VM Host Sizing (vCPU/RAM) & Backup Time Calculator
Calculate physical CPU cores, host RAM sizing with ZFS ARC cache buffer for Proxmox/ESXi, and network backup data transfer duration (RTO).
Wi-Fi Access Point & PoE Switch Capacity Calculator
Calculate Wi-Fi access point counts by coverage area and client capacity, PoE switch power budget, and minimum ISP internet line bandwidth.
Fiber Optic Loss Budget (dBm) & UTP Cable Box Calculator
Calculate GPON/EPON optical link loss budget (dBm), passive splitter loss, splicing, and estimate bulk UTP Ethernet cable boxes and RJ45s.
dBm to mW Converter & Free Space Path Loss (FSPL) Calculator
Convert RF power between dBm, milliwatts (mW), Watts, and dBW, and calculate Free Space Path Loss (FSPL) attenuation for wireless radio links.
Wireless PtP Link Budget & Fresnel Zone Calculator
Calculate received RX signal (dBm), free-space path loss FSPL, 60% Fresnel clearance, earth curvature bulge, and minimum triangle tower heights.
CCTV Lens Selection & Field of View Calculator
Calculate CCTV lens focal length recommendations (2.8mm, 4mm, 6mm, 12mm), field of view coverage width, and DORI pixel density per target distance.
CCTV DORI Distance Calculator (EN 62676-4)
Calculate EN 62676-4 CCTV DORI detection, observation, recognition, and facial identification reach distances based on sensor resolution and lens optics.
PoE Cable Voltage Drop Calculator
Calculate PoE Cat6, Cat5e, and CCA cable voltage drop, delivered terminal voltage, safe run distances, and night-time infrared reboot risks.
CCTV NVR Storage Capacity & Bandwidth Calculator
Calculate CCTV NVR storage capacity (TB), network ingress bandwidth Mbps, recording retention days, PoE budgets, and surveillance HDD recommendations.
CCTV Installation Material BOM Estimator
Estimate CCTV installation material Bill of Materials (BOM): Cat6 UTP cable boxes, RJ45 modular plugs, junction boxes, conduit pipes, and cable ties.
CCTV UPS & Battery Backup Calculator
Calculate CCTV camera, NVR, and PoE switch UPS apparent power (VA) and deep-cycle VRLA battery capacity (Ah) for power outage runtime.
Linux Cron Job Expression & Crontab Schedule Generator
POSIX 5-field cron expression generator, production crontab line builder, next 5 execution timestamps, and systemd timer unit converter.
Linux Chmod File Permissions Calculator (Octal & Symbolic)
Convert Linux chmod octal (755, 644, 4750) and symbolic (-rwxr-xr-x) permissions, calculate umask, audit 777 security risks, and view breakdown tables.
Linux Firewall Generator (UFW, Iptables & Nftables)
Generate production Linux server firewall rulesets for UFW, iptables, and /etc/nftables.conf with SSH rate-limiting and trusted subnet whitelisting.
Linux Swap Size, Swappiness & Ext4 Inode Calculator
Calculate optimal Linux swap size, vm.swappiness, vm.vfs_cache_pressure sysctl tunables, default ext4 inode count, and /swapfile creation script.
Password Entropy & Brute-Force Crack Time Calculator
Calculate cryptographic password entropy bits (E = L × log2(R)), total keyspace combinations, and brute-force crack times across Bcrypt and GPU rigs.
JWT Token Size, Base64URL Overhead & TTL Calculator
Calculate JWT token byte size (HS256, RS256, ES256, EdDSA), Base64URL overhead, 4 KB browser cookie and 8 KB Nginx header limits, and monthly bandwidth.
VPN Encryption Overhead & Tunnel MTU Calculator (WireGuard, IPsec, OpenVPN)
Calculate cryptographic encapsulation overhead, optimal tunnel MTU, TCP MSS clamping, and effective payload throughput for WireGuard, IPsec, and OpenVPN.
SIEM Security Log Storage, EPS & Audit Retention Calculator
Calculate aggregate Events Per Second (EPS), daily raw log volume, indexed Hot Storage, and compressed Cold Archive capacity for Wazuh & Elastic SIEM.
Data Storage Unit Converter (TB vs TiB, GB vs GiB, Decimal vs Binary)
Convert accurately between manufacturer decimal SI units (KB, MB, GB, TB, PB) and operating system binary IEC 80000-13 units (KiB, MiB, GiB, TiB, PiB).
Network Data Transfer, Backup Window & Sync Time Calculator
Calculate file transfer duration, offsite backup windows, and effective throughput (Mbps, MB/s, MiB/s) accounting for TCP/IP protocol overhead.
SLA Uptime, Allowed Downtime & SRE Error Budget Calculator
Calculate maximum allowed daily, monthly, and yearly downtime from SLA targets (99.9%–99.999%) or audit achieved SLA from observed incident duration.
IT Equipment Power Consumption (Watt, kWh), PUE & Electricity Cost Calculator
Calculate daily, monthly, and annual kWh energy usage, data center PUE overhead, monthly electricity bills, 220V MCB amperage, and BTU/hr heat load.
Interactive Floorplan Wi-Fi Heatmap & CCTV FoV Planner
Interactive 2D floorplan planner for estimating Wi-Fi AP 2.4/5GHz signal coverage radii and CCTV camera FoV DORI coverage cones visually.
MikroTik RouterOS .rsc Config Security Auditor
Automated security audit for MikroTik RouterOS v7 .rsc export files, detecting misconfigurations, exposed services, and generating fix scripts.
TIA-598C Fiber Color Code & RJ45 Pinout Simulator
Visualizer for TIA-598C fiber optic color codes from 1 to 288 cores, tube mapping, and RJ45 LAN pinout diagrams (T568A/T568B) with PoE pairing.
TIA-606-C Cable Label & Asset QR Code Generator
Print-ready ANSI/TIA-606-C cable wrap, patch panel strip, and asset QR tag generator for standardized, enterprise-grade structured cabling.
IT Project UAT Checklist & Handover BAST Generator
Generate formal User Acceptance Testing (UAT) checklists and project commissioning handover (BAST) documentation for enterprise IT deployments.
Multi-Timezone Maintenance Window & Cron Planner
Plan server maintenance windows across WIB, WITA, WIT, SGT, and UTC timezones with automated cron backup conflict detection and change notice.
GPON FTTH Cascade Splitter & Optical Tree Calculator
Calculate GPON/EPON optical link loss budget, simulate ODC/ODP cascade splitters (1:2 to 1:16, tap 15/85), and view ITU-T G.984 optical tree diagrams.
MAC Vendor OUI & MikroTik DHCP Lease Conflict Inspector
Inspect bulk ARP tables and MikroTik DHCP leases, identify OUI vendors, detect randomized MACs, and catch duplicate IP network conflicts instantly.
Infrastructure Spec Duel & Hardware ROI Comparator
Compare technical specifications of ZFS RAIDZ1 vs RAIDZ2 vs RAID10, CCTV H.264 vs H.265+ storage savings, and WireGuard vs IPsec vs OpenVPN throughput.
Docker, Nginx & Linux Stack Visual Composer
Visually compose production container stacks: select Nginx/Cloudflare ingress, frontend, backend API, databases & Redis. Generates SVG topology, docker-compose.yml, and UFW scripts.
API Capacity & Rate Limit Calculator
Calculate sustained & burst peak RPS (Little's Law L=λW), concurrent in-flight requests, required vCPU cores, and Nginx rate-limiting rules.
Popular Scenarios & Field Cheat Sheets
Quick answer presets for CIDR Subnetting (/24 to /32), MikroTik Multi-WAN PCC, CCTV Storage, and GPON Splitter Loss.
Enterprise IT & Network Architecture Blueprints Gallery
Save hours of design work. Select a production template below to load pre-filled engineering parameters into calculators or export everything directly to My Workspace as a Master Blueprint.
50-Room Hotel & Boarding House
Dual-ISP PCC Load Balancing + 18 Ruijie APs + 4 VLAN Segments + 16 IP PoE Cameras
24/7 Hospital & Clinical Center
Proxmox HA Cluster ZFS RAIDZ2 + FortiGate + 32 CCTVs 30-Day Retention + 3kVA Online UPS
FTTH WISP & Digital Village 250 Subs
OLT GPON 1:4 ➔ 1:8 Splitter Cascade + MikroTik RB5009 PCQ FQ-CoDel Shaper
Open-Air Resort & Eco-Lodge
Starlink High Performance + Fiber Failover + 18 Wi-Fi 6 Outdoor Mesh APs
120-Seat School / CBT Exam Lab
Structured /22 Subnetting + Linux UFW Bandwidth Cap + Local CBT Exam VM Server
Industrial Warehouse & Factory Floor
24 Long-Distance PoE Bullet Cams + Galvanized Conduit + 24U Grounded Server Rack
Server Room & NOC Cheat-Sheet Poster (A3 / A4 Print-Ready)
★ Wall EditionIPv4 CIDR Table, TIA-598C 12-Core Fiber, RJ45/PoE Pinout, GPON Loss Budget, and MTU/ZFS.
