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Range Check v1.4.0

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This is a simple module to validate IP address, check IP address version, check if IP is within a range.

This started out as range_check but it does much more than just checking ranges but since it's already got a large amount of downloads (37,115 downloads in the last month as of this writing) I'll keep the name the same even though I kinda want to change it to something better.


To set up Range Check on your Node.js server use npm.

npm install range_check

IP Functions

Check if IP is valid

var rangeCheck = require('range_check');
console.log(rangeCheck.isIP('')); //returns true or false 

Check IP version


var rangeCheck = require('range_check');
console.log(rangeCheck.ver('')); //returns 4
console.log(rangeCheck.ver('2001:4860:8006::62')); //returns 6
console.log(rangeCheck.ver('foo')); //returns 0 as invalid IP address


var rangeCheck = require('range_check');
console.log(rangeCheck.isV4('')); //true 
console.log(rangeCheck.isV4('foo')); //false 
console.log(rangeCheck.isV4('123::123')); //false 


var rangeCheck = require('range_check');
console.log(rangeCheck.isV6('123::123')); //true 
console.log(rangeCheck.isV6('foo')); //false 
console.log(rangeCheck.isV6('')); //false 


This function is useful to get a consistent IP address such for storing it in a database or when searching in a database after being stored using this. So if a V6 address was sent compacted or not, or if you searched by either version this function would make sure you get a consistent IP address for both versions. Also the possibly of saving a few bytes.

If an V6 addressed mapped as v4 is given it will convert it to V4, If any other V6 address is given it is abbreviated and plain V4 addresses are left alone. Returns null if a invalid IP

var rangeCheck = require('../range_check.js');
console.log(rangeCheck.storeIP('foo')); //null 
console.log(rangeCheck.storeIP('::ffff:')); // 
console.log(rangeCheck.storeIP('2001:0000:0111:0000:0011:0000:0001:0000')); //2001:0:111:0:11:0:1:0 
console.log(rangeCheck.storeIP('2001:0001:0000:0001:0000:0000:0000:0000')); //2001:1:0:1:: 
console.log(rangeCheck.storeIP('0000:0000:0000:0000:0000:0000:0000:0000')); //:: 
console.log(rangeCheck.storeIP('0000:0000:0000:0000:0000:0000:0000:0001')); //::1 
console.log(rangeCheck.storeIP('2041:0000:140F:0000:0000:0000:875B:131B')); //2041:0:140F::875B:131B 
console.log(rangeCheck.storeIP('2001:0001:0002:0003:0004:0005:0006:0007')); //2001:1:2:3:4:5:6:7 
console.log(rangeCheck.storeIP('')); // 


Same function as storeIP, just a clearer name when you are using it for search instead


This function is useful for displaying IP addresses, such as after grabbing it back from the database when using storeIP

If an V6 addressed mapped as v4 is given it will convert it to V4, If any other V6 address is given it is normalized into the longer version and plain V4 addresses are left alone. Returns a empty string if a invalid IP

var rangeCheck = require('../range_check.js');
console.log(rangeCheck.displayIP(null)); // '' 
console.log(rangeCheck.displayIP('::ffff:')); //'' 
console.log(rangeCheck.displayIP('2001:0:111:0:11:0:1:0')); //'2001:0000:0111:0000:0011:0000:0001:0000' 
console.log(rangeCheck.displayIP('2001:1:0:1::')); //'2001:0001:0000:0001:0000:0000:0000:0000' 
console.log(rangeCheck.displayIP('::')); //'0000:0000:0000:0000:0000:0000:0000:0000' 
console.log(rangeCheck.displayIP('::1')); //'0000:0000:0000:0000:0000:0000:0000:0001' 
console.log(rangeCheck.displayIP('2041:0:140F::875B:131B')); //'2041:0000:140F:0000:0000:0000:875B:131B' 
console.log(rangeCheck.displayIP('2001:1:2:3:4:5:6:7')); //'2001:0001:0002:0003:0004:0005:0006:0007' 
console.log(rangeCheck.displayIP('')); //'' 

Range Functions

Check if range is valid

You can use isRange if you want to validate an entire range.

var rangeCheck = require('range_check');
console.log(rangeCheck.isRange('2001:db8::/32')); //true 
console.log(rangeCheck.isRange('')); // true 
console.log(rangeCheck.isRange('qwerty')); // false 

Check if IP is within range

var rangeCheck = require('range_check');
console.log(rangeCheck.inRange('', '')); //returns true 
console.log(rangeCheck.inRange('', '')); //returns false 
console.log(rangeCheck.inRange('2001:db8:1234::1', '2001:db8::/32')); //returns true 

You can also give a list of ranges

var rangeCheck = require('range_check');
console.log(rangeCheck.inRange('', ['', ''])); //returns true