Converting Numbers to Another Base

JavaScript FAQ | Numbers FAQ | Strings and RegExp FAQ  

Question: How do I convert a number to a different base (radix)?

Answer: In JavaScript 1.1, you can use the standard method Number.toString(radix) for converting a number to a string representing that number in a non-decimal number system (e.g. to a string of binary, octal or hexadecimal digits). For example:

a = (32767).toString(16)  // result: "7fff"
b = (255).toString(8)     // result: "377"
c = (1295).toString(36)   // result: "zz"
d = (127).toString(2)     // result: "1111111"

However, in very old browsers (supporting only JavaScript 1.0) there was no standard method for this conversion. Here is a function that does the conversion of integers to an arbitrary base (radix) in JavaScript 1.0:

function toRadix(N,radix) {
 var HexN="", Q=Math.floor(Math.abs(N)), R;
 while (true) {
  HexN = "0123456789abcdefghijklmnopqrstuvwxyz".charAt(R)
       + HexN;
  if (Q==0) break;
 return ((N<0) ? "-"+HexN : HexN);

You can test this conversion right now:

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