CIDR Block & IP Range Calculator
Convert IP ranges to CIDR notation or expand CIDR blocks into starting and ending IP addresses.
Classless Inter-Domain Routing (CIDR) Block Management
CIDR notation (e.g., 10.1.0.0/24) replaces traditional Class A, B, and C networks by appending a prefix length representing active network mask bits.
CIDR aggregation minimizes global BGP routing table size by summarizing hundreds of individual subnets into single route advertisements.
Interactive CIDR Block & IP Range Calculator Workspace
Free ISP Engineering & Planning Tools
Precision planning tools for WISPs and fiber operators — RF, optical, power, addressing, and business math. No sign-up required.
Link Budget Calculator
Calculate FSPL, RSSI, and EIRP for wireless links (2.4GHz to 60GHz).
Tower Revenue Calculator
Analyze ISP tower profitability, CAPEX/OPEX, and business Break-Even Point.
GPON Splitter Calculator
Plan optical budgets for PON networks. Calculate splitter and fiber loss.
UPS Runtime Calculator
Estimate battery backup time based on load (Watts) and battery capacity (Ah).
IPv4 Subnet Calculator
CIDR to Subnet Mask, Network Address, Broadcast, and Host Range calculator.
CGNAT Calculator
Plan Carrier-Grade NAT: subscribers per public IPv4, port blocks, and pool capacity.
Data & Bandwidth Converter
Convert Mbps to Gbps, MB to GB, bits to bytes, plus a download time calculator.
Bandwidth Calculator
Plan oversubscription ratios and total backhaul capacity requirements.
ROI Comparison
Compare Kashtrix costs vs legacy platforms (Splynx/Sonar). See how much you can save.
SLA Uptime Calculator
Convert SLA uptime percentages (99.9%) to allowable downtime limits.
MAC Address Lookup
Find the hardware vendor behind any MAC address and decode the OUI bits.
DNS Lookup
Query live A, AAAA, MX, TXT, NS, CNAME and SOA records for any domain.
What Is My IP
See your public IP address, reverse DNS, ISP and location instantly.
IP Location Lookup
Geolocate any IPv4 or IPv6 address: country, city, ISP, ASN and timezone.
CIDR Calculator
Expand a CIDR block to its range, or aggregate an IP range into CIDR blocks.
IPv6 Subnet Calculator
Network, address range, expanded form and subnet counts for any IPv6 prefix.
dBm to Watt Converter
Convert RF power between dBm, mW and watts, and dB gain to a linear ratio.
CIDR Calculator
Real-World Calculation Walkthrough
Calculating CIDR properties for 10.1.0.5 with a /24 mask
Input Parameters
Calculation Output
CIDR Block & IP Range Calculator Engineering FAQs
What is CIDR route summarization?
CIDR summarization merges multiple contiguous smaller subnets (e.g., four /24 subnets) into a single larger prefix (e.g., one /22 block).
What is the smallest IPv4 prefix allowed in global BGP tables?
Most Tier-1 transit providers drop IPv4 BGP prefixes smaller than /24 to prevent routing table bloat.
What is the equivalent CIDR prefix for a single host IP?
A single host IPv4 address is represented by a /32 prefix (e.g., 192.168.1.1/32).
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IPv4 Subnet & CIDR Calculator
Calculate network address, broadcast address, subnet mask, wildcard mask, and usable host ranges for any IPv4 CIDR prefix.
IPv6 Subnet & Prefix Calculator
Calculate IPv6 expanded addresses, subnet ranges, prefix breakdowns, and total /64 subnets from any IPv6 prefix (/48, /56, /64).