If your IP address is assigned automatically, so is your subnet mask. In this case, if you’re connected to the internet, don’t worry about finding or changing your subnet mask. But, if you’re setting up a static IP address that isn’t assigned automatically, you’ll need to find the right subnet mask to get online. The easiest way to find out what subnet mask you should be using is to ask your network administrator. If that’s not possible right now, read on!
This is not foolproof, as network administrators can divide up IP ranges into many subnets. But for smaller networks, this might be all you need to do to find the subnet mask. Once signed in, compare the other device’s IP address to your static IP. Do they appear to be in the same range or from a similar-sized range? If so, using that device’s subnet mask might work. For example, if your static IP address is 192. 168. 0. 5 and the other device is 192. 168. 0. 12, having the first three octets in common means you’re likely on the same subnet. However, subnets can be broken up in a multitude of ways so there’s a chance your network administrator has sub-divided the network even further.
Spiceworks’ Subnet Calculator is easy to use if you know the IP range. Just enter the first and last IP addresses in the range, then choose 1 as the number of subnets (if you’re sure the range you’ve entered is a single subnet). Subnet Calculator and Cheat Sheet provides a subnet mask based on a starting IP address and its associated CIDR notation, which is a special value that explains how many addresses are in that range. If you’re not sure what to enter here, just refer to the CIDR cheat sheet at the bottom of the tool. For example, if you’re working with a range of 256 IP addresses (a common subnet size for homes and small offices), you’ll use /24. For /24 ranges, the subnet mask will be 255. 255. 255. 0. The cheat sheet at the bottom is also helpful if you just want to try to guess the subnet mask based on the presumed size of the subnet. For example, you’ll see that when a subnet contains 1024 IP addresses, its mask will be 255. 255. 252. 0, which is /22 in CIDR notation.
Open your Windows Settings and select Network & Internet. [2] X Trustworthy Source Microsoft Support Technical support and product information from Microsoft. Go to source For Wi-Fi, select Wi-Fi > Manage Known Networks. For Ethernet, select Ethernet, then choose your network. Click Edit under “IP assignment. " Select Manual, then choose IPv4. Update your subnet mask and other details and save.
If you’re using an ethernet connection, you will now see your IP address and subnet mask in the right panel. If you’re using Wi-Fi, continue with this method to find your subnet mask.
If you’re using an ethernet connection, you will now see your IP address and subnet mask in the right panel. If you’re using Wi-Fi, continue with this method to find your subnet mask.
If the only numbers you see are on the lower half of the screen underneath “Configure IPv6,” you are on a local IPv6 network which does not use subnet masks. If you’re having internet trouble, select Using DHCP from the drop-down menu, then click Renew DHCP Lease to receive a new IP address and subnet mask.
Select the network in the Network panel of System Preferences. Click Configure IPv4 in the menu, then select Manually. Replace the current subnet mask with the new one and save your changes. [4] X Research source
If you see “command not found,” type whereis ifconfig to get the full path, such as /sbin/ifconfig, then simply type the full path to ifconfig and press ↵ Enter.
Find the adapter name for the connection you want to modify using ifconfig.
For example, eth0 for your ethernet connection.
If the subnet mask is the only thing you need to change, use sudo ifconfig
The steps to view your subnet mask on Android will be a little different depending on your platform, such as Samsung Galaxy or stock Android.
The steps to view your subnet mask on Android will be a little different depending on your platform, such as Samsung Galaxy or stock Android.
If you don’t see this option, tap Network & Internet (or similar) and select Wi-Fi instead. [6] X Research source
If you don’t see your subnet mask, tap Advanced or similar to show more options. Some Androids connected through DHCP may not display the subnet mask at all. If you’re not able to find the subnet mask with these steps, download Termux, a free terminal app, from the Play Store. Once downloaded, open the app, type ifconfig, and press Enter. You will see your subnet mask under “wlan0. "
Select the Advanced or Manage option in your network’s settings. If you don’t see it, tap and hold the name of your wireless network in the list of networks, then tap Modify network. Tap the IP Settings option if you see it—this is common on Samsung Galaxy models. If DHCP is selected, you’ll need to change it to Static. Then, you’ll be able to modify the subnet mask, IP address, gateway, and other details.
Just above your IP address, tap Configure IP. If you have a static IP address already, you’ll see the option to modify the subnet mask here. If not, you can tap Manual and enter your new static IP address information, including your subnet and gateway address (referred to here as “router”).
