Subnet Mask Calculator

Professional IP address and subnet mask calculation tool, supporting CIDR conversion, network planning, and batch processing.

Bug report

Browser execution mode: Your data is processed in your browser and is not uploaded to the server.

Speed and Stability: Processing speed depends on your device and browser. For large batch work, the desktop version may be more stable.

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If the online tool fails to load or run, try the desktop tool.https://tools.yikeaigc.com/

Tool Usage

Return to old version

Enter network info

IP can be a host address or CIDR shorthand, e.g. 192.168.1.100 or 192.168.1.0/24.

Current page: Single calculation

IP address or CIDR

Mask type

Mask value

Common CIDR

Show binary Show bit-level representation of IP, mask, and network address. Show address properties Show Class A/B/C/D/E and properties such as private and loopback. Show wildcard mask Useful for checking ACL, routing policy, and similar configs. Show subnetting reference Show subnet count and capacity after further subnetting.

Calculation results

Batch input and file parsing

Enter IP and mask per line. Separate with comma, Tab, semicolon, or space. You can also enter 192.168.1.0/24 directly.

Processed locally

Batch textExample: 192.168.1.1,24

Choose local file

When selecting multiple files, the first 20 are shown. All files are processed. Output filenames in the download keep original names; duplicates get a number appended.

Batch calculation results

Generate subnet plan

Enter a base network, then generate network addresses, broadcast addresses, and usable ranges by subnet count, host capacity, or VLSM needs.

Planning mode

Base network

Planning method

Number of subnets needed

Hosts needed per subnet

VLSM needsEach line: name,hosts

Planning results

Instructions

Software Usage Instructions

Select a calculation page: You can use the “Single Calculation,” “Batch Calculation,” and “Subnet Planning” pages. It is recommended to set the input content and calculation options before running the calculation.
Single Calculation: Enter an IPv4 address or CIDR block, select CIDR, decimal mask, or wildcard mask, and click “Calculate Current IP” to view the network address, broadcast address, available IP range, number of hosts, and other information.
Configure display options: You can enable binary display, address attributes, wildcard mask, and subnetting reference to verify ACL configurations, network bits, and host bits.
Batch Calculation: You can paste multiple lines of data directly or select a TXT, CSV, or XLSX file. Each line supports the “IP,mask” or “IP/CIDR” format, such as 192.168.1.1,24.
Subnet Planning: After entering the base network segment, you can generate planning results by number of subnets, host capacity per subnet, or VLSM requirements, including the address range and number of available hosts for each subnet.
Save and download: You can save commonly used settings; single results can be copied or downloaded as TXT, while batch and planning results can be downloaded as CSV or a compressed package.

FAQ

A: CIDR uses a slash followed by a number to indicate the number of network bits, such as /24; a decimal mask uses a format like 255.255.255.0. /24 and 255.255.255.0 represent the same network bits.

A: In common IPv4 subnets, the network address is used to identify the network segment, and the broadcast address is used for broadcasts within that segment, so they are usually not assigned to regular devices. /31 and /32 scenarios have special uses, and the tool will display them according to the corresponding rules.

A: A wildcard mask is the inverse of a subnet mask and is commonly used in ACLs, routing policies, and other configurations. For example, 255.255.255.0 corresponds to 0.0.0.255.

A: Enter one IP and mask per line. Commas, tabs, semicolons, or spaces are supported as separators, such as 192.168.1.1,24, 10.0.0.1,255.255.0.0, and 198.51.100.8/29.

A: VLSM is suitable for network planning where different departments or business areas require different host capacities. After entering the name and number of hosts, the tool generates a network segment plan that closely matches the capacity requirements.

A: In a valid subnet mask, the binary network bits must be consecutive 1s, followed by consecutive 0s. For example, 255.255.255.0 is valid, while 255.0.255.0 is not a standard contiguous mask.