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Cost of try/catch in JavaScript

I know that in Java, using a try/catch is fairly expensive vs. a if check. Since JavaScript has the same syntax for the most part, I wrote up a simple benchmarking script to test it out. On my box, it outputs:

if avg: 0.029
try avg: 1.372

Note, that you’ll need the Firebug plugin for Firefox in order to run this.

var tryFunc = function () {
  try {
    document.getElementById("fake").innerHTML = "hi there";
  } catch (e) {
    // eat it!
  }
}

var ifFunc = function() {
  var el = document.getElementById("fake");
  if (el) {
    el.innerHTML = "hi there";
  }
};

function benchmark(name, func) {
  var repeats = 1000;
  var elapsed = 0;
  var startTime =0;
  var endTime = 0;
  for (var i=0; i< repeats; i++) {
    startTime = new Date().getTime();
    func.call();
    endTime = new Date().getTime();
    elapsed += (endTime - startTime);
  }
  console.log(name + " avg: " + (elapsed / repeats ) );
}

benchmark( "if", ifFunc );
benchmark( "try", tryFunc );