The IPv4 Subnet Calculator and IP Address CIDR Range Calculator handle address-space planning in seconds, the Reverse Subnet Mask Calculator flips mask formats without a lookup table, and the Bandwidth, Mbps, and Mbps Download Time calculators help you size circuits and justify capacity requests with hard numbers — all in one place.
The full list is ranked by how frequently network professionals reach for each tool. Check the Trending tab for what's gaining attention right now — every calculator is free, instant, and runs on any device without an account.
- Construction Calculator
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Data Transfer Rate ConverterConvert data transfer speed between bps, kbps, Mbps, Gbps, MB/s, GB/s and binary kibi/mebi/gibi units instantly. SI (1000) and IEC (1024) supported.
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IP Address Range to CIDR CalculatorConvert a start and end IPv4 address range into the smallest CIDR prefix block. Get the /prefix, block size, and address count instantly.
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IP Subnet & Host Count CalculatorCalculate usable hosts, subnet mask, wildcard mask and total addresses from any IPv4 CIDR prefix (/0 to /32). Free subnetting tool.
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Network & Broadcast Address CalculatorFree IPv4 network and broadcast address calculator. Enter an IP and CIDR prefix to get the network, broadcast, subnet mask, host range and address count.
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IP Subnet Mask CalculatorFree IPv4 subnet calculator. Enter an IP and CIDR prefix to get the subnet mask, network & broadcast address, usable host count, and full host range.
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CIDR to Subnet Mask CalculatorConvert any CIDR prefix length (/0 to /32) into its dotted-decimal subnet mask, wildcard mask, total addresses, and usable host count instantly.
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IP Address to Binary CalculatorConvert any IPv4 address to binary, a 32-bit decimal integer, and hexadecimal. Enter four octets (0-255) for instant dotted-binary output.
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Data Storage Conversion CalculatorConvert between bytes, KB, MB, GB, TB and PB using binary (1024) or decimal (1000) systems. Fast, accurate data storage unit converter.
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dBm to Watts CalculatorConvert dBm to watts and milliwatts instantly. Enter a power level in dBm to get the equivalent power in W using P = 10^((dBm−30)/10).
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Hosts per Subnet CalculatorCalculate the maximum usable hosts per IPv4 subnet from the prefix length using 2^(32−prefix) − 2. Instant CIDR host count for any /n.
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VoIP Bandwidth CalculatorCalculate VoIP bandwidth per call and total for concurrent calls. Factors in codec bitrate, packetization interval and IP/UDP/RTP header overhead.
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Free Space Path Loss CalculatorCalculate Free Space Path Loss (FSPL) in dB from distance (km) and frequency (MHz). Uses the standard 32.44 constant RF link-budget formula.
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VLSM CalculatorFree VLSM calculator: enter a base network and host requirements to get optimal subnets, prefix lengths, usable ranges, and broadcast addresses.
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Data Transfer Rate ConverterConvert data transfer rates between bps, Kbps, Mbps, Gbps, and B/s, KB/s, MB/s, GB/s instantly. Free online bandwidth and speed unit converter.
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Concurrent Users Bandwidth CalculatorCalculate the bandwidth available per user when a connection is shared. Enter total Mbps and the number of concurrent users to get per-user Mbps and Kbps.
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Usable IP Address Count CalculatorCalculate the number of usable IPv4 host addresses for any subnet prefix (/0 to /32) using usable = 2^(32 − prefix) − 2.
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Watts to dBm CalculatorConvert power in watts to dBm instantly. Free Watts to dBm calculator using dBm = 10·log10(W / 0.001) for RF, antenna, and signal power conversions.
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RF Link Budget CalculatorCalculate received RF signal power (dBm) from transmit power, antenna gains, path loss, and system losses. Free link budget calculator with EIRP.
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Wildcard Mask CalculatorConvert a subnet mask or CIDR prefix to its wildcard (inverse) mask. Each octet = 255 − mask octet. Perfect for Cisco ACLs and OSPF.
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TCP Throughput CalculatorCalculate maximum TCP throughput from window size and round-trip time (RTT). Free bandwidth-delay product tool in Mbps, Kbps and bps.
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EIRP CalculatorCalculate EIRP (Effective Isotropic Radiated Power) in dBm, dBW and watts from transmitter power, antenna gain and cable loss.
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Number of Subnets CalculatorCalculate the number of subnets created when you subnet an IPv4 network. Enter the original and new prefix lengths to find subnets, borrowed bits, and hosts.
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Hosts per Subnet CalculatorCalculate the number of usable host IP addresses per subnet from a CIDR prefix length (/8 to /32). Fast IPv4 subnetting host count tool.
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IP Address to Decimal ConverterConvert an IPv4 address (a.b.c.d) to its 32-bit decimal integer value. Enter four octets and get the exact long integer representation instantly.
Frequently asked questions
What networking tasks can these calculators help with?
The collection covers IP address planning — subnetting, CIDR notation, subnet mask conversions — along with bandwidth and throughput estimation and download time calculations. Whether you're designing a new network, troubleshooting capacity, or checking your math before a change request, there's a tool for it.
How reliable are the subnet and bandwidth results?
Subnetting calculations follow RFC-standard IPv4 address math, and bandwidth formulas use standard bit-rate relationships. Results are accurate for planning purposes. Always double-check address assignments against your actual network documentation and routing tables before deploying changes to a live environment.
Are my IP addresses or network details stored anywhere?
No. All calculations run entirely in your browser. None of the IP addresses, mask values, or capacity figures you enter are sent to or logged by our servers.
Which networking calculators are used most?
The IPv4 Subnet Calculator and IP Address CIDR Range Calculator are the most frequently used tools in this section. The Bandwidth Calculator and Mbps Download Time Calculator are also popular. The full list is sorted by usage volume; the Trending tab shows what's gaining traction right now.
Is there a fee or registration required?
None at all. Every tool is completely free, no account needed, and works on any device with a modern browser — desktop, laptop, tablet, or phone.
