Loading…
Calculate IPv4 subnets, masks, and host counts. Use for IPv4 planning; for IPv6 use ipv6-calculator. Input: CIDR or mask. Returns subnet table. 100% client-side.
IPv4 Subnet Calculator is loading — interactive editor will appear here. Use examples below to try instantly once loaded.
Press ? for keyboard shortcuts
Calculates IPv4 subnet details from CIDR notation, subnet mask, or slash-mask input. Displays network address, broadcast address, subnet mask, wildcard mask, usable host range, total and usable host counts, and a binary representation of the network address and mask.
Manually computing subnet boundaries, host ranges, and broadcast addresses is tedious and error-prone. This tool accepts multiple input formats (CIDR, subnet mask, or slash-mask) and instantly returns all critical subnet details with a binary visualization.
This tool is part of the DevStackIO platform — a collection of free online developer tools from DevStackIO. Browse more free developer resources on DevStackIO.
Network administrators, DevOps engineers configuring cloud VPCs and container networks, and students learning IP subnetting fundamentals.
Enter an IPv4 address with CIDR notation (e.g., 192.168.1.0/24), a subnet mask (e.g., 192.168.1.0 255.255.255.0), or a slash-mask (e.g., 192.168.1.0/255.255.255.0)
Press Calculate or hit Enter to compute subnet details
Review the network address, broadcast address, subnet mask, wildcard mask, and usable host range
Check the binary view to visually verify the network and host portions of the address
Input: '192.168.1.0/24' — Output: Network: 192.168.1.0, Broadcast: 192.168.1.255, Subnet Mask: 255.255.255.0, Host Range: 192.168.1.1 - 192.168.1.254, Usable Hosts: 254Input: '10.0.0.0 255.255.0.0' — Output: Network: 10.0.0.0, Broadcast: 10.0.255.255, Subnet Mask: 255.255.0.0, CIDR: /16, Usable Hosts: 65,534What input formats are supported?
CIDR notation (192.168.1.0/24), IP + subnet mask (192.168.1.0 255.255.255.0), or IP/slash-mask (192.168.1.0/255.255.255.0).
What is a wildcard mask?
It is the bitwise inverse of the subnet mask, commonly used in ACLs and routing protocols.
Why does /31 show a different host range?
/31 subnets use point-to-point conventions where both addresses can be assigned to hosts.
Authoritative specifications, standards, and in-depth reading for IPv4 Subnet Calculator.
Supports: CIDR (192.168.1.0/24), IP + mask (192.168.1.0 255.255.255.0), or IP/slash-mask (192.168.1.0/255.255.255.0)
Calculate IPv6 subnets, expansion, and compression. Use for IPv6 planning; for IPv4 use ipv4-subnet-calculator. Input: IPv6/CIDR. Returns subnet details. 100% client-side.
Calculate network, broadcast, and host range from CIDR. Use for subnet math; for geo lookup use ip-lookup. Input: IP/CIDR. Returns network details. 100% client-side.
Convert IPv4 between dotted, hex, integer, and binary. Use for format shifts; for subnet math use ipv4-subnet-calculator. Input: IPv4 address. Returns all formats. 100% client-side.
Expand CIDR or dash ranges into IP lists. Use when enumerating hosts; for subnet calc use ipv4-subnet-calculator. Input: range text. Returns IP list. 100% client-side.
Parse raw HTTP headers into readable name-value pairs. Use when debugging responses; for URL parts use url-parser. Input: header text ≤10MB. Returns table of headers. 100% client-side.
Split any URL into protocol, host, path, and query params. Use when inspecting URLs; for encoding query strings use url-encoder. Input: URL text. Returns component table. 100% client-side.
Parse user-agent strings into browser, OS, and device. Use when debugging traffic; for live device data use device-information. Input: UA string. Returns parsed fields. 100% client-side.
Look up DNS records for any domain. Use when checking DNS; for IP geo use ip-lookup. Input: domain name. Returns A, MX, TXT records. 100% client-side.