Convert IPv4 to a 32-bit integer. For prefix length n, subnet mask is: mask = ((2^n − 1) << (32 − n)). Network = IP & mask. Broadcast = Network | (~mask). Usable range: [Network+1 .. Broadcast−1] when n ≤ 30; otherwise no usable host. Total hosts = 2^(32 − n). Usable hosts = max(0, Total − 2) when n ≤ 30.
IPv6 has 128 bits. Network = IP & mask where first n bits of the mask are 1. Total addresses = 2^(128 − n). There is no broadcast in IPv6; first/last usage depends on policy, so we display [network .. last].
`;
shadow.appendChild(wrap);// DOM refs
var v4ip = shadow.getElementById('v4ip');
var v4prefix = shadow.getElementById('v4prefix');
var v4res = shadow.getElementById('v4res');
var v4net = shadow.getElementById('v4-net');
var v4bc = shadow.getElementById('v4-bc');
var v4range = shadow.getElementById('v4-range');
var v4mask = shadow.getElementById('v4-mask');
var v4wild = shadow.getElementById('v4-wild');
var v4total = shadow.getElementById('v4-total');
var v4usable = shadow.getElementById('v4-usable');
var v4cidr = shadow.getElementById('v4-cidr');var v6ip = shadow.getElementById('v6ip');
var v6prefix = shadow.getElementById('v6prefix');
var v6res = shadow.getElementById('v6res');
var v6net = shadow.getElementById('v6-net');
var v6first = shadow.getElementById('v6-first');
var v6last = shadow.getElementById('v6-last');
var v6total = shadow.getElementById('v6-total');
var v6cidr = shadow.getElementById('v6-cidr');// Populate select options
var v4opts = [30,29,28,27,26,25,24,23,22,21,20,19,18,17,16,15,14,13,12,11,10,9,8];
v4opts.forEach(function(n){ var o=document.createElement('option'); o.value=n; o.textContent=maskFromPrefix(n)+' /'+n; v4prefix.appendChild(o); });
v4prefix.value = 30;var v6opts = [];
for(var i=64;i<=128;i++) v6opts.push(i);
v6opts.forEach(function(n){ var o=document.createElement('option'); o.value=n; o.textContent='/' + n; v6prefix.appendChild(o); });
v6prefix.value = 64;// Utils IPv4
function ipToInt(ip){ var p=ip.split('.'); if(p.length!==4) return NaN; var x=0; for(var i=0;i<4;i++){ var a=Number(p[i]); if(!Number.isInteger(a)||a<0||a>255) return NaN; x=(x<<8)|a; } return x>>>0; }
function intToIp(x){ return [(x>>>24)&255,(x>>>16)&255,(x>>>8)&255,x&255].join('.'); }
function maskFromPrefix(n){ var m=(n===0)?0: (~((1<<(32-n))-1))>>>0; return intToIp(m); }
function wildcardFromMask(maskInt){ return intToIp((~maskInt)>>>0); }// IPv4 Calculate
function calcV4(){
var n = parseInt(v4prefix.value,10);
var ipInt = ipToInt(v4ip.value.trim());
if(!Number.isFinite(ipInt)){ v4res.style.display='none'; return; }
var maskInt = ipToInt(maskFromPrefix(n));
var network = (ipInt & maskInt)>>>0;
var broadcast = (network | (~maskInt>>>0))>>>0;
var total = Math.pow(2, 32-n);
var usable = (n<=30) ? Math.max(0, total-2) : 0;
var first = (n<=30 && usable>0)? (network+1)>>>0 : network;
var last = (n<=30 && usable>0)? (broadcast-1)>>>0 : broadcast;v4net.textContent = intToIp(network);
v4bc.textContent = intToIp(broadcast);
v4range.textContent = intToIp(first) + ' — ' + intToIp(last);
v4mask.textContent = intToIp(maskInt);
v4wild.textContent = wildcardFromMask(maskInt);
v4total.textContent = total.toLocaleString();
v4usable.textContent = usable.toLocaleString();
v4cidr.textContent = v4ip.value.trim() + '/' + n;
v4res.style.display = 'block';
}// IPv6 helpers (minimal, string-based bit masking for display purposes)
function expandIPv6(addr){
var parts = addr.split('::');
if(parts.length>2) return null;
var left = parts[0].split(':').filter(Boolean);
var right = (parts[1]||'').split(':').filter(Boolean);
var missing = 8 - (left.length + right.length);
if(missing < 0) return null;
var mid = new Array(missing).fill('0');
var full = left.concat(mid).concat(right).map(function(h){ return h.padStart(4,'0'); });
if(full.length!==8) return null;
return full.join(':');
}
function ipv6ToBigInt(addr){ var ex=expandIPv6(addr); if(!ex) return null; var p=ex.split(':'); var v=0n; for(var i=0;i<8;i++){ var n=BigInt(parseInt(p[i],16)); if(n<0n||n>0xffffn) return null; v=(v<<16n)|n; } return v; }
function bigIntToIPv6(x){ var parts=[]; for(var i=0;i<8;i++){ var seg = Number((x >> BigInt(16*(7-i))) & 0xffffn); parts.push(seg.toString(16)); } return parts.join(':').replace(/(^|:)0{1,3}/g,'$1'); }function calcV6(){
try{
var n = parseInt(v6prefix.value,10);
var val = v6ip.value.trim();
var ip = ipv6ToBigInt(val);
if(ip===null){ v6res.style.display='none'; return; }
var mask = (n===0)? 0n : (~((1n << BigInt(128-n)) - 1n)) & ((1n<<128n)-1n);
var network = ip & mask;
var total = (n<=127)? (1n << BigInt(128-n)) : 1n;
var first = network; // IPv6: show same network as first
var last = network + (total - 1n);v6net.textContent = bigIntToIPv6(network);
v6first.textContent = bigIntToIPv6(first);
v6last.textContent = bigIntToIPv6(last);
v6total.textContent = total.toString();
v6cidr.textContent = val + '/' + n;
v6res.style.display = 'block';
}catch(e){ v6res.style.display='none'; }
}// Buttons
shadow.getElementById('v4calc').addEventListener('click', calcV4);
shadow.getElementById('v4clear').addEventListener('click', function(){ v4ip.value=''; v4res.style.display='none'; });
shadow.getElementById('v6calc').addEventListener('click', calcV6);
shadow.getElementById('v6clear').addEventListener('click', function(){ v6ip.value=''; v6res.style.display='none'; });
});
}
if(document.readyState==='loading') document.addEventListener('DOMContentLoaded', init); else init();
})();
IP Subnet Calculator Dekho Hacks: 10 Game-Changing Methods
IP Subnet Calculator Dekho : In today’s interconnected digital landscape, efficient network management has become the backbone of successful IT operations. Whether you’re a seasoned network engineer, an aspiring IT student, or a business owner managing your company’s infrastructure, understanding and implementing proper subnetting is crucial. An IP subnet calculator serves as your digital companion, transforming complex mathematical calculations into instant, accurate results.
Network subnetting— the process of dividing large networks into smaller, more manageable segments—can be overwhelming when done manually. One miscalculation can lead to IP conflicts, security vulnerabilities, or inefficient address allocation. This is where a reliable subnet calculator becomes indispensable, offering precision and speed that manual calculations simply cannot match.
This comprehensive guide will walk you through everything you need to know about IP subnet calculators, from basic concepts to advanced applications. You’ll discover how these tools work, explore different types available, and learn practical techniques that will elevate your network management skills. Let’s dive into the world of subnetting made simple.
