Simple test to see how long it takes a random alphanumeric function to generate a duplicate string.

randomAlphaNumString.js

/**
 *************************************************************************************************************
 *****  This will no longer lock up your browser tab, but it will not find a match for a very long time   ****
 *****                      Do not run this in a tab you do not want to reload                            ****
 *************************************************************************************************************
 * 
 * This was just me playing around trying to see if I could get a duplicate random string 
 * when using the Math.random().toString(radix) method. 
 * 
 * I had planned to implement web workers with this as well so that I could let it 
 * keep running forever and just see how long it took to get a duplicate string, but setTimout and setInterval work just fine...
 */


var radix = 32;
var getRandomString = function() { return Math.random().toString(radix).slice(2); };
var stringToMatch = getRandomString();
window.matchesArray = [];
window.matchesTried = 0;
var startTime = performance.now();
var generatedStrings = [];
var timeElapsed = 0;
var endTime;
var newStringInterval;
var matchCheckInterval = 1000;

var generateNewString = function generateNewString() {
    generatedStrings.push(getRandomString());
};
var checkForMatches = function checkForMatches() {
  endTime = performance.now() - startTime;
  if (generatedStrings.indexOf(stringToMatch) === -1) {
      matchesTried += generatedStrings.length - 1;
      generatedStrings = [];
      console.log('no match found from ' + matchesTried + ' different matches in ' + (endTime/1000)/60 + ' minutes.');
      return setTimeout(checkForMatches, matchCheckInterval);
  } else {
    console.log('Matched on ' + stringToMatch + ' in ' + (endTime/1000)/60 + ' minutes');
  }
};
newStringInterval = setInterval(generateNewString, 0);
setTimeout(checkForMatches, matchCheckInterval);