How to check what is the network mask of a public IP

7 posts · originally from https://geek.digit.in/community/threads/how-to-check-what-is-the-network-mask-of-a-public-ip.211215/

Hello Everyone

My router from my ISP is receiving a public IP 83.7.x.x. How can I find out what is the mask of the IP? I tried some web sites who tell you what is your IP, but no luck.

thx

Here try this :

*www.icontime.com/support/knowledge...-how-to-find-the-subnet-mask-gateway-and-dns/

@topgear i don't think this will help in finding subnet mask for a router ip as this looks for the ip of the current machine on which the command is run i.e. the PC and not the router.

vidhubhushan said:
@topgear i don't think this will help in finding subnet mask for a router ip as this looks for the ip of the current machine on which the command is run i.e. the PC and not the router.

Oh .. I misunderstood. Op wants know the subnet mask of the IP address assigned by the ISP ? There are manual ways to do it but Op might find this more handy :

*www.calculator.net/ip-subnet-calculator.html

I doubt this calculator gives correct data. What are the manuals ways to confirm it?

Thx

Here are two links for that :

*www.shorttutorials.com/calculate-subnet-mask/index.html

*www.pluralsight.com/blog/it-ops/simplify-routing-how-to-organize-your-network-into-smaller-subnets

What is the reason you need to know the subnet mask of your IPv4?

While you have already been provided most links in above posts, just wondering if the WAN Status page of your router is not showing these details? Most routers do.
What is your router make/model?

My ZTE F670L as well as DLink router show the subnet at WAN Status. See the screenshots.
Additionally I put my ZTE router in Bridge mode and directly plugged in my PC to it and dialed PPPoE from my PC to Airtel. Now my single PC is directly on Airtel WAN and IPCONFIG /ALL provides me all the details including the public IP and subnet. Generally, if it’s PPPoE most likely public ip is using /32 bit mask so it will be 255.255.255.255. That’s what I always get on my Airtel PPPoE no matter what class of IPv4 I get.