diff --git a/Src/Newtonsoft.Json.Tests/Utilities/ConvertUtilsTests.cs b/Src/Newtonsoft.Json.Tests/Utilities/ConvertUtilsTests.cs
index 8687a910..94dd81b1 100644
--- a/Src/Newtonsoft.Json.Tests/Utilities/ConvertUtilsTests.cs
+++ b/Src/Newtonsoft.Json.Tests/Utilities/ConvertUtilsTests.cs
@@ -39,6 +39,7 @@ namespace Newtonsoft.Json.Tests.Utilities
     [TestFixture]
     public class ConvertUtilsTests : TestFixtureBase
     {
+#if HAS_CUSTOM_DOUBLE_PARSE
         private void AssertDoubleTryParse(string s, ParseResult expectedResult, double? expectedValue)
         {
             double d;
@@ -157,6 +158,7 @@ namespace Newtonsoft.Json.Tests.Utilities
 
             AssertDoubleTryParse("4.94065645841247E+555", ParseResult.Overflow, null);
         }
+#endif
 
         private void AssertDecimalTryParse(string s, ParseResult expectedResult, decimal? expectedValue)
         {
diff --git a/Src/Newtonsoft.Json/JsonTextReader.cs b/Src/Newtonsoft.Json/JsonTextReader.cs
index f15a685d..5fafa20d 100644
--- a/Src/Newtonsoft.Json/JsonTextReader.cs
+++ b/Src/Newtonsoft.Json/JsonTextReader.cs
@@ -2058,9 +2058,10 @@ namespace Newtonsoft.Json
                 }
                 else
                 {
+                    string number = _stringReference.ToString();
+
                     double value;
-                    ParseResult parseResult = ConvertUtils.DoubleTryParse(_stringReference.Chars, _stringReference.StartIndex, _stringReference.Length, out value);
-                    if (parseResult == ParseResult.Success)
+                    if (double.TryParse(number, NumberStyles.Float, CultureInfo.InvariantCulture, out value))
                     {
                         numberValue = value;
                     }
@@ -2137,9 +2138,10 @@ namespace Newtonsoft.Json
                         }
                         else
                         {
+                            string number = _stringReference.ToString();
+
                             double d;
-                            parseResult = ConvertUtils.DoubleTryParse(_stringReference.Chars, _stringReference.StartIndex, _stringReference.Length, out d);
-                            if (parseResult == ParseResult.Success)
+                            if (double.TryParse(number, NumberStyles.Float, CultureInfo.InvariantCulture, out d))
                             {
                                 numberValue = d;
                             }
diff --git a/Src/Newtonsoft.Json/Utilities/ConvertUtils.cs b/Src/Newtonsoft.Json/Utilities/ConvertUtils.cs
index 8de7ad1a..3a8542b9 100644
--- a/Src/Newtonsoft.Json/Utilities/ConvertUtils.cs
+++ b/Src/Newtonsoft.Json/Utilities/ConvertUtils.cs
@@ -930,6 +930,7 @@ namespace Newtonsoft.Json.Utilities
             return ParseResult.Success;
         }
 
+#if HAS_CUSTOM_DOUBLE_PARSE
         private static class IEEE754
         {
             /// <summary>
@@ -1356,6 +1357,7 @@ namespace Newtonsoft.Json.Utilities
             value = IEEE754.PackDouble(isNegative, mantissa, exponent);
             return double.IsInfinity(value) ? ParseResult.Overflow : ParseResult.Success;
         }
+#endif
 
         public static ParseResult DecimalTryParse(char[] chars, int start, int length, out decimal value)
         {