diff --git a/src/ol/base.js b/src/ol/base.js
index cbba821d9f..1c2a6bd1ca 100644
--- a/src/ol/base.js
+++ b/src/ol/base.js
@@ -16,3 +16,24 @@ ol.error = function(message) {
  * @define {boolean}
  */
 ol.error.VERBOSE_ERRORS = true;
+
+/**
+ * @define {boolean}
+ */
+ol.CHECK_KEYS = true;
+
+/**
+ * @param {Object} obj Object.
+ * @param {!Array.<string>} allowedKeys Allowed keys.
+ */
+ol.base.checkKeys = function(obj, allowedKeys) {
+    if (ol.CHECK_KEYS) {
+        var keys = goog.object.getKeys(obj);
+        goog.array.forEach(allowedKeys, function(allowedKey) {
+            goog.array.remove(keys, allowedKey);
+        });
+        if (!goog.array.isEmpty(keys)) {
+            ol.error('object contains invalid keys: ' + keys.join(', '));
+        }
+    }
+};