diff --git a/tests/base64.html b/tests/base64.html
new file mode 100644
index 0000000..b66fc42
--- /dev/null
+++ b/tests/base64.html
@@ -0,0 +1,74 @@
+<!DOCTYPE html> 
+<html xmlns="http://www.w3.org/1999/xhtml"> 
+  <head> 
+    <title>Native Base64 Tests</title> 
+    <script src="include/util.js"></script> 
+  </head> 
+  <body> 
+        <h1>Native Base64 Tests</h1> 
+ 
+        <br> 
+        Messages:<br> 
+        <textarea id="debug" style="font-size: 9px;" cols=80 rows=25></textarea> 
+    
+        <br>
+  </body> 
+ 
+<script> 
+    function debug(str) {
+        console.log(str);
+        cell = $('debug');
+        cell.innerHTML += str + "\n";
+        cell.scrollTop = cell.scrollHeight;
+    }
+
+    function assertRun(code, result) {
+        try {
+            var actual = eval(code);
+        } catch (exc) {
+            debug("FAIL: '" + code + "' threw an exception");
+            fail += 1;
+            return false;
+        }
+        if (actual !== result) {
+            debug("FAIL: '" + code + "' returned '" + actual + "', expected '" + result + "'");
+            fail += 1;
+            return false;
+        }
+        debug("PASS: '" + code + "' returned expected '" + result +"'");
+        pass += 1;
+        return true;
+    }
+
+    window.onload = function() {
+        var str;
+        debug('onload');
+        fail = 0;
+        pass = 0;
+        assertRun('window.btoa("hello world")', 'aGVsbG8gd29ybGQ=');
+        assertRun('window.atob("aGVsbG8gd29ybGQ=")', 'hello world');
+        assertRun('window.atob("YQ==")', 'a');
+        assertRun('window.atob("YWI=")', 'ab');
+        assertRun('window.atob("YWJj")', 'abc');
+        assertRun('window.atob("YWJjZA==")', 'abcd');
+        assertRun('window.atob("YWJjZGU=")', 'abcde');
+        assertRun('window.atob("YWJjZGVm")', 'abcdef');
+        assertRun('window.btoa("a")', 'YQ==');
+        assertRun('window.btoa("ab")', 'YWI=');
+        assertRun('window.btoa("abc")', 'YWJj');
+        assertRun('window.btoa("abcd")', 'YWJjZA==');
+        assertRun('window.btoa("abcde")', 'YWJjZGU=');
+        assertRun('window.btoa("abcdef")', 'YWJjZGVm');
+        assertRun('window.btoa("abcdefg")', 'YWJjZGVmZw==');
+        assertRun('window.btoa("abcdefgh")', 'YWJjZGVmZ2g=');
+
+        assertRun('typeof window.btoa', 'function');
+        assertRun('window.btoa("")', '');
+        assertRun('window.btoa(null)', '');
+        assertRun('window.atob(window.btoa(window))', window.toString()); // "[object DOMWindow]"
+        assertRun('window.btoa("\\u0080\\u0081")', 'gIE=');
+
+        debug("Tests failed: " + fail);
+        debug("Tests passed: " + pass);
+    }
+</script> 
