Subnet Calculator

Hi all,
Few months ago I've decided to build online subnet calculator after I didn't find any online tool that works for me the tool support ipv4 / ipv6 and i also added a subnetting guide https://subnet.ninja i'd like to get feedbacks on the guide or on the calculator

10x

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Comments

rob42

It seems to work fine; good job!

If I could make one suggestion, it would be to have the HEX represented in upper case, rather than lowercase.

There's a very good IPv4 Subnet Calculator available from this forum. Have you tried it?

subnet.ninja

10x for the feedback i really appreciate it, about the IPv6 HEX it was a long argue about the pros and cons when we start implement IPv6 in networks but then we see RFC5952 that say in section 4.3 : " The characters "a", "b", "c", "d", "e", and "f" in an IPv6 address MUST be represented in lowercase." so we go with the lowercase.... I see the Calculator in the forum, but its a program that running only on Microsoft machines... when i decided to build the online calculator i wanted a tool that will run on any device for daily use. do you think that an option to divide prefix to subnetworks is needed ?
P.S - have you also looked on the subnetting guide ?

rob42

You're very welcome, re: feedback.

You've obviously done your research by reference to the RFC, and I have not, so go with it.

I'm somewhat 'old school', having been using computers and computer code for the past 30 years or so. For me, seeing HEX notation written in lowercase is a little odd, and from a readability perspective, strange, as it’s not easy on the eye. Back in the day, HEX notation was always (well almost always) represented in uppercase, and I also note that the study books that I'm using (ICND1 100-101 & ICND2 200-101) also have the HEX notation of IPv6 in uppercase. But I accept that things change and I'll have to get used to seeing IPv6 in lowercase.

You ask...

do you think that an option to divide prefix to subnetworks is needed ?

As you can probably surmise, I'm new the world of IPv6 and have yet to study the subject in any great depth, so I'll let other, more knowledgeable people, offer an opinion on that.

While I accept that on-line apps are 'bang on trend', I have issues with them: what if one is unable to get an internet connection? What good are on-line tools and apps then? This is why I prefer to use stand-alone apps and tools.

Just a thought: I use a web browser based password generator that works off-line URL]http://passwordchart.com/[/URL][URL="http://passwordchart.com/"[/URL]. Could your app be made to work like that? It’s most probably more work and time than you feel is worth committing to, but like I say, just a thought.

By the way, I'm in no way criticising the very good work (and I'm guessing over many hours) that you've done; my hat goes off to you. This is just an observation.

I've not had a chance to study the subnetting guide that you've written. It would not be doing it any justice to simply skim over it and then come to a judgement, so when I have the time, I'll read it, in depth.

My best regards to you.

Uriah7

I come from a computer science background (New to IT) and we have always used lowercase hexadecimal representation. I would leave it lowercase. The only places I have ever seen hexadecimal notation represented in upper case is in textbooks and my assumption is that it is used for readability.

The prefix/subnet split seems fine to me. It doesn't hurt.

Everything else looks great. Good job!

pevangel

Good job taking this on and getting something that works pretty well. I tried a couple of inputs and noticed a few issues:

192.0.2.0 is being classified as a private address.
The link, "See IP Space Info", on the results page is broken. It points to https://subnet.ninja/ip-space/ but I believe it should be pointing to https://subnet.ninja/ip-address-space/.
Try a /31 address space and you'll see a couple of issues.

subnet.ninja

10x for the reply:
I changed the 192.0.2.0/24 network type to "Documentation". fixed the broken link to the address space and switched the first and last host on /31 network (hope that I didn't miss anything....)
Thank again !