diff --git a/lib/csharp/src/Protocol/TJSONProtocol.cs b/lib/csharp/src/Protocol/TJSONProtocol.cs
index 4081d6e..88d554e 100644
--- a/lib/csharp/src/Protocol/TJSONProtocol.cs
+++ b/lib/csharp/src/Protocol/TJSONProtocol.cs
@@ -505,7 +505,7 @@
         private void WriteJSONDouble(double num)
         {
             context.Write();
-            String str = num.ToString(CultureInfo.InvariantCulture);
+            String str = num.ToString("R", CultureInfo.InvariantCulture);
             bool special = false;
 
             switch (str[0])
diff --git a/lib/csharp/test/ThriftTest/TestClient.cs b/lib/csharp/test/ThriftTest/TestClient.cs
index c09a801..f0297d0 100644
--- a/lib/csharp/test/ThriftTest/TestClient.cs
+++ b/lib/csharp/test/ThriftTest/TestClient.cs
@@ -358,6 +358,14 @@
                 Console.WriteLine("*** FAILED ***");
                 returnCode |= ErrorBaseTypes;
             }
+            Console.Write("testDouble(-0.000341012439638598279)");
+            dub = client.testDouble(-0.000341012439638598279);
+            Console.WriteLine(" = " + dub);
+            if (-0.000341012439638598279 != dub)
+            {
+                Console.WriteLine("*** FAILED ***");
+                returnCode |= ErrorBaseTypes;
+            }
 
             byte[] binOut = PrepareTestData(true);
             Console.Write("testBinary(" + BytesToHex(binOut) + ")");
diff --git a/lib/py/src/protocol/TJSONProtocol.py b/lib/py/src/protocol/TJSONProtocol.py
index 9e25f67..7807a6c 100644
--- a/lib/py/src/protocol/TJSONProtocol.py
+++ b/lib/py/src/protocol/TJSONProtocol.py
@@ -176,9 +176,9 @@
     self.context.write()
     self.trans.write(json.dumps(string, ensure_ascii=False))
 
-  def writeJSONNumber(self, number):
+  def writeJSONNumber(self, number, formatter='{}'):
     self.context.write()
-    jsNumber = str(number)
+    jsNumber = formatter.format(number)
     if self.context.escapeNum():
       jsNumber = "%s%s%s" % (QUOTE, jsNumber, QUOTE)
     self.trans.write(jsNumber)
@@ -467,7 +467,8 @@
     self.writeJSONNumber(i64)
 
   def writeDouble(self, dbl):
-    self.writeJSONNumber(dbl)
+    # 17 significant digits should be just enough for any double precision value.
+    self.writeJSONNumber(dbl, '{:.17g}')
 
   def writeString(self, string):
     self.writeJSONString(string)
diff --git a/test/cpp/src/TestClient.cpp b/test/cpp/src/TestClient.cpp
index 1ab4d21..2736ee8 100644
--- a/test/cpp/src/TestClient.cpp
+++ b/test/cpp/src/TestClient.cpp
@@ -106,6 +106,29 @@
   }
 }
 
+// Workaround for absense of C++11 "auto" keyword.
+template <typename T>
+bool print_eq(T expected, T actual) {
+  cout << "(" << actual << ")" << endl;
+  if (expected != actual) {
+    cout << "*** FAILED ***" << endl << "Expected: " << expected << " but got: " << actual << endl;
+    return false;
+  }
+  return true;
+}
+
+#define BASETYPE_IDENTITY_TEST(func, value)                                                        \
+  cout << #func "(" << value << ") = ";                                                            \
+  try {                                                                                            \
+    if (!print_eq(value, testClient.func(value)))                                                  \
+      return_code |= ERR_BASETYPES;                                                                \
+  } catch (TTransportException&) {                                                                 \
+    throw;                                                                                         \
+  } catch (exception & ex) {                                                                       \
+    cout << "*** FAILED ***" << endl << ex.what() << endl;                                         \
+    return_code |= ERR_BASETYPES;                                                                  \
+  }
+
 int main(int argc, char** argv) {
   int ERR_BASETYPES = 1;
   int ERR_STRUCTS = 2;
@@ -388,11 +411,47 @@
     /**
      * DOUBLE TEST
      */
-    printf("testDouble(-5.2098523)");
-    double dub = testClient.testDouble(-5.2098523);
-    printf(" = %f\n", dub);
-    if ((dub - (-5.2098523)) > 0.001) {
-      printf("*** FAILED ***\n");
+    // Comparing double values with plain equality because Thrift handles full precision of double
+    BASETYPE_IDENTITY_TEST(testDouble, 0.0);
+    BASETYPE_IDENTITY_TEST(testDouble, -1.0);
+    BASETYPE_IDENTITY_TEST(testDouble, -5.2098523);
+    BASETYPE_IDENTITY_TEST(testDouble, -0.000341012439638598279);
+    BASETYPE_IDENTITY_TEST(testDouble, pow(2, 32));
+    BASETYPE_IDENTITY_TEST(testDouble, pow(2, 32) + 1);
+    BASETYPE_IDENTITY_TEST(testDouble, pow(2, 53) - 1);
+    BASETYPE_IDENTITY_TEST(testDouble, -pow(2, 32));
+    BASETYPE_IDENTITY_TEST(testDouble, -pow(2, 32) - 1);
+    BASETYPE_IDENTITY_TEST(testDouble, -pow(2, 53) + 1);
+
+    try {
+      double expected = pow(10, 307);
+      cout << "testDouble(" << expected << ") = ";
+      double actual = testClient.testDouble(expected);
+      cout << "(" << actual << ")" << endl;
+      if (expected - actual > pow(10, 292)) {
+        cout << "*** FAILED ***" << endl
+             << "Expected: " << expected << " but got: " << actual << endl;
+      }
+    } catch (TTransportException&) {
+      throw;
+    } catch (exception& ex) {
+      cout << "*** FAILED ***" << endl << ex.what() << endl;
+      return_code |= ERR_BASETYPES;
+    }
+
+    try {
+      double expected = pow(10, -292);
+      cout << "testDouble(" << expected << ") = ";
+      double actual = testClient.testDouble(expected);
+      cout << "(" << actual << ")" << endl;
+      if (expected - actual > pow(10, -307)) {
+        cout << "*** FAILED ***" << endl
+             << "Expected: " << expected << " but got: " << actual << endl;
+      }
+    } catch (TTransportException&) {
+      throw;
+    } catch (exception& ex) {
+      cout << "*** FAILED ***" << endl << ex.what() << endl;
       return_code |= ERR_BASETYPES;
     }
 
diff --git a/test/py/TestClient.py b/test/py/TestClient.py
index 7e3daf2..3a74353 100755
--- a/test/py/TestClient.py
+++ b/test/py/TestClient.py
@@ -158,6 +158,7 @@
     self.assertEqual(self.client.testDouble(-5.235098235), -5.235098235)
     self.assertEqual(self.client.testDouble(0), 0)
     self.assertEqual(self.client.testDouble(-1), -1)
+    self.assertEqual(self.client.testDouble(-0.000341012439638598279), -0.000341012439638598279)
 
   def testBinary(self):
     if isinstance(self, JSONTest):
diff --git a/test/rb/integration/TestClient.rb b/test/rb/integration/TestClient.rb
index 8fd6336..6aec596 100755
--- a/test/rb/integration/TestClient.rb
+++ b/test/rb/integration/TestClient.rb
@@ -130,7 +130,7 @@
 
   def test_double
     p 'test_double'
-    val = 3.14
+    val = 3.14159265358979323846
     assert_equal(@client.testDouble(val), val)
     assert_equal(@client.testDouble(-val), -val)
     assert_kind_of(Float, @client.testDouble(val))