diff --git a/tests/src/App/Expression.cpp b/tests/src/App/Expression.cpp
index 39c3c4fb15..69fbce094c 100644
--- a/tests/src/App/Expression.cpp
+++ b/tests/src/App/Expression.cpp
@@ -1,7 +1,33 @@
+// SPDX-License-Identifier: LGPL-2.1-or-later
+/***************************************************************************
+ *   Copyright (c) 2023 Werner Mayer <wmayer[at]users.sourceforge.net>     *
+ *   Copyright (c) 2025 Pieter Hijma <info@pieterhijma.net>                 *
+ *                                                                         *
+ *   This file is part of FreeCAD.                                         *
+ *                                                                         *
+ *   FreeCAD is free software: you can redistribute it and/or modify it    *
+ *   under the terms of the GNU Lesser General Public License as           *
+ *   published by the Free Software Foundation, either version 2.1 of the  *
+ *   License, or (at your option) any later version.                       *
+ *                                                                         *
+ *   FreeCAD is distributed in the hope that it will be useful, but        *
+ *   WITHOUT ANY WARRANTY; without even the implied warranty of            *
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU      *
+ *   Lesser General Public License for more details.                       *
+ *                                                                         *
+ *   You should have received a copy of the GNU Lesser General Public      *
+ *   License along with FreeCAD. If not, see                               *
+ *   <https://www.gnu.org/licenses/>.                                      *
+ *                                                                         *
+ **************************************************************************/
+
 #include <gtest/gtest.h>
 
 #include <src/App/InitApplication.h>
 
+#include "App/Document.h"
+#include "App/DocumentObject.h"
+#include "App/Expression.h"
 #include "App/ExpressionParser.h"
 #include "App/ExpressionTokenizer.h"
 
@@ -300,4 +326,86 @@ TEST_F(Expression, test_e_rad)
     EXPECT_EQ(op->toString(), "e rad");
     op.release();
 }
+
+class Evaluate: public ::testing::Test
+{
+protected:
+    static void SetUpTestSuite()
+    {
+        tests::initApplication();
+    }
+
+    void SetUp() override
+    {
+        _doc_name = App::GetApplication().getUniqueDocumentName("test");
+        _this_doc = App::GetApplication().newDocument(_doc_name.c_str(), "testUser");
+        _this_obj = _this_doc->addObject("App::VarSet");
+    }
+
+    void TearDown() override
+    {
+        App::GetApplication().closeDocument(_doc_name.c_str());
+    }
+
+    App::DocumentObject* this_obj() { return _this_obj; }
+
+private:
+    std::string _doc_name;
+    App::Document* _this_doc {};
+    App::DocumentObject* _this_obj {};
+};
+
+// Various test for evaluating and simplifying expressions
+// Each "evaluate" test has an equivalent "simplify" test
+TEST_F(Evaluate, test_evaluate_simple)
+{
+    App::Expression* e = App::ExpressionParser::parse(this_obj(), "1 + 2");
+    App::Expression* evaluated = e->eval();
+    EXPECT_EQ(e->toString(), "1 + 2");
+    EXPECT_EQ(evaluated->toString(), "3");
+}
+
+TEST_F(Evaluate, test_simplify_simple)
+{
+    App::Expression* e = App::ExpressionParser::parse(this_obj(), "1 + 2");
+    App::Expression* simplified = e->simplify();
+    EXPECT_EQ(e->toString(), "1 + 2");
+    EXPECT_EQ(simplified->toString(), "3");
+}
+
+TEST_F(Evaluate, test_evaluate_function)
+{
+    App::Expression* e = App::ExpressionParser::parse(this_obj(), "sqrt(4)");
+    App::Expression* evaluated = e->eval();
+    EXPECT_EQ(e->toString(), "sqrt(4)");
+    EXPECT_EQ(evaluated->toString(), "2");
+}
+
+TEST_F(Evaluate, test_simplify_function)
+{
+    App::Expression* e = App::ExpressionParser::parse(this_obj(), "sqrt(4)");
+    App::Expression* simplified = e->simplify();
+    EXPECT_EQ(e->toString(), "sqrt(4)");
+    EXPECT_EQ(simplified->toString(), "2");
+}
+
+TEST_F(Evaluate, test_evaluate_refer_to_var)
+{
+    auto* prop = freecad_cast<App::PropertyFloat*>(this_obj()->addDynamicProperty("App::PropertyFloat", "Var"));
+    prop->setValue(2.0);
+    App::Expression* e = App::ExpressionParser::parse(this_obj(), "sqrt(2 + Var)");
+    App::Expression* evaluated = e->eval();
+    EXPECT_EQ(e->toString(), "sqrt(2 + Var)");
+    EXPECT_EQ(evaluated->toString(), "2");
+}
+
+TEST_F(Evaluate, test_simplify_refer_to_var)
+{
+    auto* prop = freecad_cast<App::PropertyFloat*>(this_obj()->addDynamicProperty("App::PropertyFloat", "Var"));
+    prop->setValue(2.0);
+    App::Expression* e = App::ExpressionParser::parse(this_obj(), "sqrt(2 + Var)");
+    App::Expression* simplified = e->simplify();
+    EXPECT_EQ(e->toString(), "sqrt(2 + Var)");
+    EXPECT_EQ(simplified->toString(), "sqrt(2 + Var)");
+}
 // clang-format on