diff --git a/libs/openFrameworks/types/ofRectangle.cpp b/libs/openFrameworks/types/ofRectangle.cpp
index 5cb2bd5f270..d91df9a5684 100644
--- a/libs/openFrameworks/types/ofRectangle.cpp
+++ b/libs/openFrameworks/types/ofRectangle.cpp
@@ -438,8 +438,8 @@ bool ofRectangle::inside(const glm::vec3& p) const {
 
 //----------------------------------------------------------
 bool ofRectangle::inside(const glm::vec2& p) const {
-	return p.x > getMinX() && p.y > getMinY() &&
-		   p.x < getMaxX() && p.y < getMaxY();
+	return p.x >= getMinX() && p.y >= getMinY() &&
+		   p.x <= getMaxX() && p.y <= getMaxY();
 }
 
 //----------------------------------------------------------
diff --git a/tests/types/rectangleTests/src/main.cpp b/tests/types/rectangleTests/src/main.cpp
new file mode 100644
index 00000000000..0b3dd3f939a
--- /dev/null
+++ b/tests/types/rectangleTests/src/main.cpp
@@ -0,0 +1,77 @@
+#include "ofMain.h"
+#include "ofAppNoWindow.h"
+#include "ofxUnitTests.h"
+
+class ofApp: public ofxUnitTestsApp{
+	void run(){
+		// Test case from Issue #4871
+		// ofRectangle(0, 0, 100, 100).intersects(ofPoint(0, 50), ofPoint(50, 0))
+		// should return true because the line segment has both endpoints on the rectangle boundary
+		ofRectangle rect1(0, 0, 100, 100);
+		ofxTest(rect1.intersects(glm::vec2(0, 50), glm::vec2(50, 0)),
+			"Issue #4871: Line segment with endpoints on rectangle boundary should intersect");
+
+		// Additional boundary tests
+		// Points exactly on corners
+		ofRectangle rect2(0, 0, 100, 100);
+		ofxTest(rect2.inside(glm::vec2(0, 0)), "Bottom-left corner should be inside");
+		ofxTest(rect2.inside(glm::vec2(100, 0)), "Bottom-right corner should be inside");
+		ofxTest(rect2.inside(glm::vec2(0, 100)), "Top-left corner should be inside");
+		ofxTest(rect2.inside(glm::vec2(100, 100)), "Top-right corner should be inside");
+
+		// Points on edges
+		ofRectangle rect3(0, 0, 100, 100);
+		ofxTest(rect3.inside(glm::vec2(50, 0)), "Point on bottom edge should be inside");
+		ofxTest(rect3.inside(glm::vec2(50, 100)), "Point on top edge should be inside");
+		ofxTest(rect3.inside(glm::vec2(0, 50)), "Point on left edge should be inside");
+		ofxTest(rect3.inside(glm::vec2(100, 50)), "Point on right edge should be inside");
+
+		// Points clearly inside
+		ofRectangle rect4(0, 0, 100, 100);
+		ofxTest(rect4.inside(glm::vec2(50, 50)), "Center point should be inside");
+		ofxTest(rect4.inside(glm::vec2(25, 25)), "Interior point should be inside");
+
+		// Points clearly outside
+		ofRectangle rect5(0, 0, 100, 100);
+		ofxTest(!rect5.inside(glm::vec2(-1, 50)), "Point left of rectangle should be outside");
+		ofxTest(!rect5.inside(glm::vec2(101, 50)), "Point right of rectangle should be outside");
+		ofxTest(!rect5.inside(glm::vec2(50, -1)), "Point below rectangle should be outside");
+		ofxTest(!rect5.inside(glm::vec2(50, 101)), "Point above rectangle should be outside");
+
+		// Line intersection tests - both endpoints inside
+		ofRectangle rect6(0, 0, 100, 100);
+		ofxTest(rect6.intersects(glm::vec2(25, 25), glm::vec2(75, 75)),
+			"Line with both endpoints inside should intersect");
+
+		// Line intersection tests - both endpoints outside, but line crosses
+		ofRectangle rect7(0, 0, 100, 100);
+		ofxTest(rect7.intersects(glm::vec2(-10, 50), glm::vec2(110, 50)),
+			"Line crossing horizontally should intersect");
+		ofxTest(rect7.intersects(glm::vec2(50, -10), glm::vec2(50, 110)),
+			"Line crossing vertically should intersect");
+
+		// Line intersection tests - one endpoint inside, one outside
+		ofRectangle rect8(0, 0, 100, 100);
+		ofxTest(rect8.intersects(glm::vec2(50, 50), glm::vec2(150, 150)),
+			"Line with one endpoint inside should intersect");
+
+		// Line intersection tests - both endpoints outside, line doesn't cross
+		ofRectangle rect9(0, 0, 100, 100);
+		ofxTest(!rect9.intersects(glm::vec2(-10, -10), glm::vec2(-5, -5)),
+			"Line completely outside should not intersect");
+
+		// Diagonal line through corners (boundary case)
+		ofRectangle rect10(0, 0, 100, 100);
+		ofxTest(rect10.intersects(glm::vec2(0, 0), glm::vec2(100, 100)),
+			"Diagonal line through corners should intersect");
+	}
+};
+
+//========================================================================
+int main( ){
+    ofInit();
+    auto window = std::make_shared<ofAppNoWindow>();
+    auto app = std::make_shared<ofApp>();
+    ofRunApp(window, app);
+    return ofRunMainLoop();
+}