diff --git a/calculator/calculator.app.js b/calculator/calculator.app.js
index acef778..df5f087 100644
--- a/calculator/calculator.app.js
+++ b/calculator/calculator.app.js
@@ -217,7 +217,7 @@ function toExponential(num, precision) {
     sign = "-";
     num = -num;
   }
-  var exp = Math.floor(Math.log10(num));
+  var exp = Math.floor(Math.log(num) / Math.LN10);
   var mantissa = num / Math.pow(10, exp);
 
   var mantissaFixed = mantissa.toFixed(precision);
@@ -452,10 +452,10 @@ function buttonPress(val) {
       break;
     case 'log':
       if (results != null) {
-        results = Math.log10(results);
+        results = Math.log(results) / Math.LN10;
         displayOutput(results);
       } else if (currNumber != null) {
-        currNumber = Math.log10(currNumber);
+        currNumber = Math.log(currNumber) / Math.LN10;
         displayOutput(currNumber);
       }
       hasPressedNumber = false;