Free ISP Tools

Engineering calculators for WISP & fiber networks

Precision planning tools for WISPs and fiber operators — RF, optical, power, addressing and business math. No sign-up required.

17 free tools Real-time results Vendor neutral

Link Budget Calculator

Calculate FSPL, RSSI, and EIRP for wireless links (2.4GHz to 60GHz).

Open calculator

Tower Revenue Calculator

Analyze ISP tower profitability, CAPEX/OPEX, and business Break-Even Point.

Open calculator

GPON Splitter Calculator

Plan optical budgets for PON networks. Calculate splitter and fiber loss.

Open calculator

UPS Runtime Calculator

Estimate battery backup time based on load (Watts) and battery capacity (Ah).

Open calculator

IPv4 Subnet Calculator

CIDR to Subnet Mask, Network Address, Broadcast, and Host Range calculator.

Open calculator

CGNAT Calculator

Plan Carrier-Grade NAT: subscribers per public IPv4, port blocks, and pool capacity.

Open calculator

Data & Bandwidth Converter

Convert Mbps to Gbps, MB to GB, bits to bytes, plus a download time calculator.

Open calculator

Bandwidth Calculator

Plan oversuspcription ratios and total backhaul capacity requirements.

Open calculator

ROI Comparison

Compare ISPbox costs vs other platforms. See how much you can save.

Open calculator

SLA Uptime Calculator

Convert SLA uptime percentages (99.9%) to allowable downtime limits.

Open calculator

MAC Address Lookup

Find the hardware vendor behind any MAC address and decode the OUI bits.

Open calculator

DNS Lookup

Query live A, AAAA, MX, TXT, NS, CNAME and SOA records for any domain.

Open calculator

What Is My IP

See your public IP address, reverse DNS, ISP and location instantly.

Open calculator

IP Location Lookup

Geolocate any IPv4 or IPv6 address: country, city, ISP, ASN and timezone.

Open calculator

CIDR Calculator

Expand a CIDR block to its range, or aggregate an IP range into CIDR blocks.

Open calculator

IPv6 Subnet Calculator

Network, address range, expanded form and subnet counts for any IPv6 prefix.

Open calculator

dBm to Watt Converter

Convert RF power between dBm, mW and watts, and dB gain to a linear ratio.

Open calculator

Why use ISPbox tools?

We build professional-grade engineering calculators for Wireless ISPs (WISPs) and fiber operators. Save time on complex calculations for link budgets, optical distribution, power backup systems, and business planning.