diff --git a/src/share/exprtk_utility.hpp b/src/share/exprtk_utility.hpp
new file mode 100644
index 000000000..fc9cbd847
--- /dev/null
+++ b/src/share/exprtk_utility.hpp
@@ -0,0 +1,50 @@
+#pragma once
+
+#define exprtk_disable_string_capabilities
+#define exprtk_disable_rtl_io
+#define exprtk_disable_rtl_io_file
+#define exprtk_disable_rtl_vecops
+
+#include <exprtk/exprtk.hpp>
+
+namespace krbn {
+namespace exprtk_utility {
+inline double eval(const std::string& expression_string,
+                   std::vector<std::pair<std::string, double>> constants) {
+  exprtk::symbol_table<double> symbol_table;
+  symbol_table.add_constants(); // pi, epsilon and inf
+  for (auto&& [name, value] : constants) {
+    symbol_table.add_constant(name, value);
+  }
+
+  exprtk::expression<double> expression;
+  expression.register_symbol_table(symbol_table);
+
+  exprtk::parser<double> parser;
+  parser.compile(expression_string, expression);
+
+  return expression.value();
+}
+
+inline exprtk::expression<double> compile(const std::string& expression_string,
+                                          std::vector<std::pair<std::string, double>> constants,
+                                          std::vector<std::pair<std::string, double&>> variables) {
+  exprtk::symbol_table<double> symbol_table;
+  symbol_table.add_constants(); // pi, epsilon and inf
+  for (auto&& [name, value] : constants) {
+    symbol_table.add_constant(name, value);
+  }
+  for (auto&& [name, value] : variables) {
+    symbol_table.add_variable(name, value);
+  }
+
+  exprtk::expression<double> expression;
+  expression.register_symbol_table(symbol_table);
+
+  exprtk::parser<double> parser;
+  parser.compile(expression_string, expression);
+
+  return expression;
+}
+} // namespace exprtk_utility
+} // namespace krbn
diff --git a/tests/src/exprtk_utility/CMakeLists.txt b/tests/src/exprtk_utility/CMakeLists.txt
new file mode 100644
index 000000000..1f0c3be6d
--- /dev/null
+++ b/tests/src/exprtk_utility/CMakeLists.txt
@@ -0,0 +1,21 @@
+cmake_minimum_required(VERSION 3.9)
+
+include(../../tests.cmake)
+
+project(karabiner_test)
+
+include_directories(${CMAKE_CURRENT_LIST_DIR}/../../../src/vendor/duktape-2.7.0/src)
+include_directories(${CMAKE_CURRENT_LIST_DIR}/../../../src/vendor/duktape-2.7.0/extras/console)
+include_directories(${CMAKE_CURRENT_LIST_DIR}/../../../src/vendor/duktape-2.7.0/extras/module-node)
+
+# Suppress duktape warnings
+add_compile_options(-Wno-deprecated-declarations)
+add_compile_options(-Wno-unused-but-set-variable)
+
+add_executable(
+  karabiner_test
+  src/test.cpp
+  ../../../src/vendor/duktape-2.7.0/src/duktape.c
+  ../../../src/vendor/duktape-2.7.0/extras/console/duk_console.c
+  ../../../src/vendor/duktape-2.7.0/extras/module-node/duk_module_node.c
+)
diff --git a/tests/src/exprtk_utility/Makefile b/tests/src/exprtk_utility/Makefile
new file mode 100644
index 000000000..2940b8362
--- /dev/null
+++ b/tests/src/exprtk_utility/Makefile
@@ -0,0 +1,6 @@
+all: build_make
+	./build/karabiner_test
+
+clean: clean_builds
+
+include ../Makefile.rules
diff --git a/tests/src/exprtk_utility/src/test.cpp b/tests/src/exprtk_utility/src/test.cpp
new file mode 100644
index 000000000..b14bfde7d
--- /dev/null
+++ b/tests/src/exprtk_utility/src/test.cpp
@@ -0,0 +1,36 @@
+#include "exprtk_utility.hpp"
+#include <boost/ut.hpp>
+
+int main(void) {
+  using namespace boost::ut;
+  using namespace boost::ut::literals;
+  using namespace std::literals;
+
+  "exprtk_utility::eval"_test = [] {
+    auto actual = krbn::exprtk_utility::eval("cos(radian) * magnitude",
+                                             {
+                                                 {"radian", 0.78539816339},
+                                                 {"magnitude", 3.5},
+                                             });
+    expect(2.47487_d == actual);
+  };
+
+  "exprtk_utility::compile"_test = [] {
+    double radian = 0.0;
+    double magnitude = 1.0;
+
+    auto expression = krbn::exprtk_utility::compile("cos(radian) * magnitude",
+                                                    {},
+                                                    {
+                                                        {"radian", radian},
+                                                        {"magnitude", magnitude},
+                                                    });
+    expect(1.0_d == expression.value());
+
+    radian = 0.78539816339;
+    magnitude = 3.5;
+    expect(2.47487_d == expression.value());
+  };
+
+  return 0;
+}