diff --git a/.gitignore b/.gitignore
index 9682782..6aa9699 100644
--- a/.gitignore
+++ b/.gitignore
@@ -11,6 +11,7 @@
 /doc/doxyfile
 /dist/
 /.cache/
+/.vscode/
 
 # MSVC project files:
 *.sln
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 8920544..92a4d5e 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -72,7 +72,7 @@ project(jsoncpp
         # 2. ./include/json/version.h
         # 3. ./CMakeLists.txt
         # IMPORTANT: also update the PROJECT_SOVERSION!!
-        VERSION 1.9.5 # <major>[.<minor>[.<patch>[.<tweak>]]]
+        VERSION 1.10.0 # <major>[.<minor>[.<patch>[.<tweak>]]]
         LANGUAGES CXX)
 
 message(STATUS "JsonCpp Version: ${PROJECT_VERSION_MAJOR}.${PROJECT_VERSION_MINOR}.${PROJECT_VERSION_PATCH}")
diff --git a/include/json/reader.h b/include/json/reader.h
index 46975d8..9898197 100644
--- a/include/json/reader.h
+++ b/include/json/reader.h
@@ -324,6 +324,8 @@ public:
    * - `"allowSpecialFloats": false or true`
    *   - If true, special float values (NaNs and infinities) are allowed and
    *     their values are lossfree restorable.
+   * - `"allowHexadecimal": false or true`
+   *   - If true, allow hexadecimal (eg 0xFFFF) to be used as unsigned integers.
    * - `"skipBom": false or true`
    *   - If true, if the input starts with the Unicode byte order mark (BOM),
    *     it is skipped.
diff --git a/src/lib_json/json_reader.cpp b/src/lib_json/json_reader.cpp
index 1ac5e81..0b4dde2 100644
--- a/src/lib_json/json_reader.cpp
+++ b/src/lib_json/json_reader.cpp
@@ -875,6 +875,7 @@ public:
   bool failIfExtra_;
   bool rejectDupKeys_;
   bool allowSpecialFloats_;
+  bool allowHexadecimal_;
   bool skipBom_;
   size_t stackLimit_;
 }; // OurFeatures
@@ -914,6 +915,7 @@ private:
     tokenArrayEnd,
     tokenString,
     tokenNumber,
+    tokenHexadecimal,
     tokenTrue,
     tokenFalse,
     tokenNull,
@@ -952,11 +954,14 @@ private:
   bool readString();
   bool readStringSingleQuote();
   bool readNumber(bool checkInf);
+  bool readHexadecimal();
   bool readValue();
   bool readObject(Token& token);
   bool readArray(Token& token);
   bool decodeNumber(Token& token);
   bool decodeNumber(Token& token, Value& decoded);
+  bool decodeHexadecimal(Token& token);
+  bool decodeHexadecimal(Token& token, Value& decoded);
   bool decodeString(Token& token);
   bool decodeString(Token& token, String& decoded);
   bool decodeDouble(Token& token);
@@ -1078,6 +1083,9 @@ bool OurReader::readValue() {
   case tokenNumber:
     successful = decodeNumber(token);
     break;
+  case tokenHexadecimal:
+    successful = decodeHexadecimal(token);
+    break;
   case tokenString:
     successful = decodeString(token);
     break;
@@ -1191,6 +1199,16 @@ bool OurReader::readToken(Token& token) {
     ok = readComment();
     break;
   case '0':
+    if(match("x", 1)) {
+      token.type_ = tokenHexadecimal;
+      ok = features_.allowHexadecimal_;
+      readHexadecimal();
+    }
+    else {
+      token.type_ = tokenNumber;
+      readNumber(false);
+    }
+    break;
   case '1':
   case '2':
   case '3':
@@ -1419,6 +1437,20 @@ bool OurReader::readNumber(bool checkInf) {
   }
   return true;
 }
+
+bool OurReader::readHexadecimal(void) {
+  Location p = current_;
+  for (; p < end_; ++p)
+  {
+    char c = *p;
+    if ( (c < '0' || c > '9')
+      && (c < 'a' || c > 'f')
+      && (c < 'A' || c > 'F') ) break;
+  }
+  current_ = p;
+  return true;
+}
+
 bool OurReader::readString() {
   Char c = 0;
   while (current_ != end_) {
@@ -1639,6 +1671,41 @@ bool OurReader::decodeNumber(Token& token, Value& decoded) {
   return true;
 }
 
+bool OurReader::decodeHexadecimal(Token& token) {
+  Value decoded;
+  if (!decodeHexadecimal(token, decoded))
+    return false;
+  currentValue().swapPayload(decoded);
+  currentValue().setOffsetStart(token.start_ - begin_);
+  currentValue().setOffsetLimit(token.end_ - begin_);
+  return true;
+}
+
+bool OurReader::decodeHexadecimal(Token& token, Value& decoded) {
+  Location current = token.start_;
+  if (current < token.end_ && *current == '0') ++current;
+  if (current < token.end_ && *current == 'x') ++current;
+  Json::LargestUInt value = 0;
+  if (current >= token.end_)
+    return addError("Zero hexadecimal digits.", token);
+  if (current + (sizeof(value) * 2) < token.end_)
+    return addError("Token too long to be unsigned integer.", token, current);
+  for (; current < token.end_; ++current) {
+    Char c = *current;
+    if (c >= 'a')
+      c -= 'a' - 10;
+    else if (c >= 'A')
+      c -= 'A' - 10;
+    else if (c >= '0')
+      c -= '0';
+    else
+      return addError("Contains non-hexadecimal digits.", token, current);
+    value = value << 4 | static_cast<Value::UInt>(c);
+  }
+  decoded = value;
+  return true;
+}
+
 bool OurReader::decodeDouble(Token& token) {
   Value decoded;
   if (!decodeDouble(token, decoded))
@@ -1908,6 +1975,7 @@ CharReader* CharReaderBuilder::newCharReader() const {
   features.failIfExtra_ = settings_["failIfExtra"].asBool();
   features.rejectDupKeys_ = settings_["rejectDupKeys"].asBool();
   features.allowSpecialFloats_ = settings_["allowSpecialFloats"].asBool();
+  features.allowHexadecimal_ = settings_["allowHexadecimal"].asBool();
   features.skipBom_ = settings_["skipBom"].asBool();
   return new OurCharReader(collectComments, features);
 }
@@ -1925,6 +1993,7 @@ bool CharReaderBuilder::validate(Json::Value* invalid) const {
       "failIfExtra",
       "rejectDupKeys",
       "allowSpecialFloats",
+      "allowHexadecimal",
       "skipBom",
   };
   for (auto si = settings_.begin(); si != settings_.end(); ++si) {
diff --git a/src/test_lib_json/main.cpp b/src/test_lib_json/main.cpp
index a6f21c4..b676092 100644
--- a/src/test_lib_json/main.cpp
+++ b/src/test_lib_json/main.cpp
@@ -3556,6 +3556,98 @@ JSONTEST_FIXTURE_LOCAL(CharReaderAllowZeroesTest, issue176) {
   }
 }
 
+struct CharReaderAllowHexadecimal : JsonTest::TestCase {};
+
+JSONTEST_FIXTURE_LOCAL(CharReaderAllowHexadecimal, disallowHex) {
+  Json::CharReaderBuilder b;
+  CharReaderPtr reader(b.newCharReader());
+  Json::Value root;
+  Json::String errs;
+  {
+    char const doc[] = R"({ "a":0x9, "b":0xf, "c":0xF })";
+    bool ok = reader->parse(doc, doc + std::strlen(doc), &root, &errs);
+    JSONTEST_ASSERT(!ok);
+    JSONTEST_ASSERT_STRING_EQUAL(
+        "* Line 1, Column 7\n"
+        "  Syntax error: value, object or array expected.\n",
+        errs);
+  }
+}
+
+JSONTEST_FIXTURE_LOCAL(CharReaderAllowHexadecimal, hexObject) {
+  Json::CharReaderBuilder b;
+  b.settings_["allowHexadecimal"] = true;
+  Json::Value invalid;
+  JSONTEST_ASSERT(b.validate(&invalid)) << invalid;
+  CharReaderPtr reader(b.newCharReader());
+  {
+    Json::Value root;
+    Json::String errs;
+    char const doc[] = R"({ "a":0x9, "b":0xf, "c":0xF })";
+    bool ok = reader->parse(doc, doc + std::strlen(doc), &root, &errs);
+    JSONTEST_ASSERT(ok);
+    JSONTEST_ASSERT_STRING_EQUAL("", errs);
+    JSONTEST_ASSERT_EQUAL(3u, root.size());
+    JSONTEST_ASSERT_EQUAL(0x9u, root.get("a", 0).asUInt());
+    JSONTEST_ASSERT_EQUAL(0xfu, root.get("b", 0).asUInt());
+    JSONTEST_ASSERT_EQUAL(0xFu, root.get("c", 0).asUInt());
+  }
+}
+
+JSONTEST_FIXTURE_LOCAL(CharReaderAllowHexadecimal, hexNumbers) {
+  Json::CharReaderBuilder b;
+  b.settings_["allowHexadecimal"] = true;
+  CharReaderPtr reader(b.newCharReader());
+
+  struct TestData {
+    bool ok;
+    Json::LargestUInt out;
+    Json::String in;
+  };
+  constexpr int _ = 0; // ignored
+  const TestData test_data[] = {
+      {true, 99, "99"}, // regular number
+      {true, 0x99, "0x99"}, // hexadecimal number
+      {false, _, "AA"}, // missing prefix
+      {false, _, "xAA"}, // partial prefix
+      {true, 0xAA, "0xAA"}, // with prefix
+      {true, 0x00, "0x00"}, // zero
+      {true, 0x0123456789, "0x0123456789"}, // numeric hex
+      {true, 0xABCDEF, "0xABCDEF"}, // uppercase-letter hex
+      {true, 0xabcdef, "0xabcdef"}, // lowercase-letter hex
+#ifdef JSON_HAS_INT64
+      {true, 0xFfffFfffFfffFfff, "0xFfffFfffFfffFfff"}, // max
+      {false, _, "0x1FfffFfffFfffFfff"}, // too long
+#else
+      {true, 0xFfffFfff, "0xFfffFfff"}, // max
+      {false, _, "0x1FfffFfff"}, // too long
+#endif
+      {false, _, "0x000000000000000000000000000000000000000"}, // too long
+      {false, _, "x"}, // leading x
+      {false, _, "0x"}, // empty number
+      {false, _, "0xx"} // extra x
+  };
+  for (const auto& td : test_data) {
+    Json::Value root;
+    Json::String errs;
+    const char* c0 = td.in.c_str();
+    const char* c1 = c0 + td.in.size();
+    bool ok = reader->parse(c0, c1, &root, &errs);
+    JSONTEST_ASSERT(td.ok == ok) << "in: " << td.in;
+    if (td.ok)
+    {
+      JSONTEST_ASSERT_STRING_EQUAL("", errs);
+      JSONTEST_ASSERT(root.isUInt64());
+      if (root.isUInt64())
+        JSONTEST_ASSERT_EQUAL(td.out, root.asLargestUInt());
+    }
+    else
+    {
+      JSONTEST_ASSERT(errs.size() > 0);
+    }
+  }
+}
+
 struct CharReaderAllowSpecialFloatsTest : JsonTest::TestCase {};
 
 JSONTEST_FIXTURE_LOCAL(CharReaderAllowSpecialFloatsTest, specialFloat) {