Hopefully this is another easy question for you all ... I have a number variable, and I want it to be formatted with commas (like 3,000 instead of 3000). My API lets the user select a bunch of polygons and it calculates a population total in the background. The number comes back correct, I just can't seem to figure out how to format it .... function sumVeterans(features) { var imputedSum = 0; //summarize the cummulative gas production to display dojo.forEach(features, function(feature) { imputedSum = imputedSum + feature.attributes.ImputedVeteran; }); //dojo.byId('messages').innerHTML = "Total Veterans: " + imputedSum + ""; var formattedImputedSum = imputedSum dojo.byId('messages').innerHTML = "Total Veterans: " + imputedSum + ""; }