diff --git a/JsonGenerator/JsonObjectBase.cpp b/JsonGenerator/JsonObjectBase.cpp
index 32772d19..c05e1825 100644
--- a/JsonGenerator/JsonObjectBase.cpp
+++ b/JsonGenerator/JsonObjectBase.cpp
@@ -4,15 +4,12 @@
 */
 
 #include "JsonObjectBase.h"
-#include <string.h> // for strcmp
 
 using namespace ArduinoJson::Generator;
 using namespace ArduinoJson::Internals;
 
-
 JsonValue JsonObjectBase::nullValue;
 
-
 size_t JsonObjectBase::printTo(Print& p) const
 {
     size_t n = 0;
@@ -47,9 +44,7 @@ JsonValue& JsonObjectBase::operator[](char const* key)
 
     for (int i = count; i > 0; --i)
     {
-        bool keyMatches = strcmp(p->key, key) == 0;
-
-        if (keyMatches)
+        if (p->matches(key))
             return p->value;
 
         p++;
@@ -70,4 +65,19 @@ JsonValue& JsonObjectBase::operator[](char const* key)
 
     value->reset();
     return *value;
+}
+
+bool JsonObjectBase::containsKey(char const* key) const
+{
+    KeyValuePair* p = items;
+
+    for (int i = count; i > 0; --i)
+    {
+        if (p->matches(key))
+            return true;
+
+        p++;
+    }
+
+    return false;
 }
\ No newline at end of file
diff --git a/JsonGenerator/JsonObjectBase.h b/JsonGenerator/JsonObjectBase.h
index 4bcb4ad3..3514fa53 100644
--- a/JsonGenerator/JsonObjectBase.h
+++ b/JsonGenerator/JsonObjectBase.h
@@ -7,6 +7,7 @@
 
 #include "JsonPrintable.h"
 #include "EscapedString.h"
+#include <string.h> // for strcmp
 
 namespace ArduinoJson
 {
@@ -18,6 +19,8 @@ namespace ArduinoJson
 
             JsonValue& operator[](const char*);
 
+            bool containsKey(const char*) const;
+
             template<typename T>
             void add(const char* key, T value)
             {
@@ -40,6 +43,11 @@ namespace ArduinoJson
             {
                 const char* key;
                 JsonValue   value;
+
+                bool matches(const char* candidateKey) const
+                {
+                    return strcmp(key, candidateKey) == 0;
+                }
             };
 
             JsonObjectBase(KeyValuePair* items, int capacity)
diff --git a/JsonGeneratorTests/JsonObject_Indexer_Tests.cpp b/JsonGeneratorTests/JsonObject_Indexer_Tests.cpp
index 33e714ef..69a67de0 100644
--- a/JsonGeneratorTests/JsonObject_Indexer_Tests.cpp
+++ b/JsonGeneratorTests/JsonObject_Indexer_Tests.cpp
@@ -35,12 +35,16 @@ namespace JsonGeneratorTests
 
         void mustContain(const char* key, const char* expected)
         {
+            Assert::IsTrue(object.containsKey(key));
+
             const char* actual = object[key];
             Assert::AreEqual(expected, actual);
         }
 
         void mustNotContain(const char* key)
         {
+            Assert::IsFalse(object.containsKey(key));
+
             const char* actual = object[key];
             Assert::IsNull(actual);
         }