diff --git a/Userland/Libraries/LibGUI/Widget.cpp b/Userland/Libraries/LibGUI/Widget.cpp
index d613aed0bd..80cfc8265f 100644
--- a/Userland/Libraries/LibGUI/Widget.cpp
+++ b/Userland/Libraries/LibGUI/Widget.cpp
@@ -780,16 +780,18 @@ void Widget::set_font_fixed_width(bool fixed_width)
         set_font(Gfx::FontDatabase::the().get(Gfx::FontDatabase::the().default_font().family(), m_font->presentation_size(), m_font->weight(), m_font->slope()));
 }
 
-void Widget::set_min_size(Gfx::IntSize const& size)
+void Widget::set_min_size(UISize const& size)
 {
+    VERIFY(size.width().is_one_of(SpecialDimension::Regular, SpecialDimension::Shrink));
     if (m_min_size == size)
         return;
     m_min_size = size;
     invalidate_layout();
 }
 
-void Widget::set_max_size(Gfx::IntSize const& size)
+void Widget::set_max_size(UISize const& size)
 {
+    VERIFY(size.width().is_one_of(SpecialDimension::Regular, SpecialDimension::Grow));
     if (m_max_size == size)
         return;
     m_max_size = size;
diff --git a/Userland/Libraries/LibGUI/Widget.h b/Userland/Libraries/LibGUI/Widget.h
index 449872a876..12bc8e7519 100644
--- a/Userland/Libraries/LibGUI/Widget.h
+++ b/Userland/Libraries/LibGUI/Widget.h
@@ -18,6 +18,7 @@
 #include <LibGUI/Forward.h>
 #include <LibGUI/GML/AST.h>
 #include <LibGUI/Margins.h>
+#include <LibGUI/UIDimensions.h>
 #include <LibGfx/Color.h>
 #include <LibGfx/Forward.h>
 #include <LibGfx/Orientation.h>
@@ -80,40 +81,43 @@ public:
         return layout;
     }
 
-    Gfx::IntSize min_size() const { return m_min_size; }
-    void set_min_size(Gfx::IntSize const&);
-    void set_min_size(int width, int height) { set_min_size({ width, height }); }
+    UISize min_size() const { return m_min_size; }
+    void set_min_size(UISize const&);
+    void set_min_size(UIDimension width, UIDimension height) { set_min_size({ width, height }); }
 
-    int min_width() const { return m_min_size.width(); }
-    int min_height() const { return m_min_size.height(); }
-    void set_min_width(int width) { set_min_size(width, min_height()); }
-    void set_min_height(int height) { set_min_size(min_width(), height); }
+    UIDimension min_width() const { return m_min_size.width(); }
+    UIDimension min_height() const { return m_min_size.height(); }
+    void set_min_width(UIDimension width) { set_min_size(width, min_height()); }
+    void set_min_height(UIDimension height) { set_min_size(min_width(), height); }
 
-    Gfx::IntSize max_size() const { return m_max_size; }
-    void set_max_size(Gfx::IntSize const&);
-    void set_max_size(int width, int height) { set_max_size({ width, height }); }
+    UISize max_size() const { return m_max_size; }
+    void set_max_size(UISize const&);
+    void set_max_size(UIDimension width, UIDimension height) { set_max_size({ width, height }); }
 
-    int max_width() const { return m_max_size.width(); }
-    int max_height() const { return m_max_size.height(); }
-    void set_max_width(int width) { set_max_size(width, max_height()); }
-    void set_max_height(int height) { set_max_size(max_width(), height); }
+    UIDimension max_width() const { return m_max_size.width(); }
+    UIDimension max_height() const { return m_max_size.height(); }
+    void set_max_width(UIDimension width) { set_max_size(width, max_height()); }
+    void set_max_height(UIDimension height) { set_max_size(max_width(), height); }
 
-    void set_fixed_size(Gfx::IntSize const& size)
+    void set_fixed_size(UISize const& size)
     {
+        VERIFY(size.has_only_int_values());
         set_min_size(size);
         set_max_size(size);
     }
 
-    void set_fixed_size(int width, int height) { set_fixed_size({ width, height }); }
+    void set_fixed_size(UIDimension width, UIDimension height) { set_fixed_size({ width, height }); }
 
-    void set_fixed_width(int width)
+    void set_fixed_width(UIDimension width)
     {
+        VERIFY(width.is_int());
         set_min_width(width);
         set_max_width(width);
     }
 
-    void set_fixed_height(int height)
+    void set_fixed_height(UIDimension height)
     {
+        VERIFY(height.is_int());
         set_min_height(height);
         set_max_height(height);
     }
@@ -377,8 +381,8 @@ private:
     NonnullRefPtr<Gfx::Font> m_font;
     String m_tooltip;
 
-    Gfx::IntSize m_min_size { -1, -1 };
-    Gfx::IntSize m_max_size { -1, -1 };
+    UISize m_min_size { SpecialDimension::Shrink };
+    UISize m_max_size { SpecialDimension::Grow };
     Margins m_grabbable_margins;
 
     bool m_fill_with_background_color { false };