diff --git a/source/blender/editors/armature/pose_slide.cc b/source/blender/editors/armature/pose_slide.cc
index 75076890659..1768b8ad5a6 100644
--- a/source/blender/editors/armature/pose_slide.cc
+++ b/source/blender/editors/armature/pose_slide.cc
@@ -72,10 +72,6 @@
 
 using blender::Vector;
 
-/* Pixel distance from 0% to 100%. */
-#define SLIDE_PIXEL_DISTANCE (300 * U.pixelsize)
-#define OVERSHOOT_RANGE_DELTA 0.2f
-
 /* **************************************************** */
 /* A) Push & Relax, Breakdowner */
 
diff --git a/source/blender/editors/screen/screen_ops.cc b/source/blender/editors/screen/screen_ops.cc
index 20c82f949fc..1a8b5251131 100644
--- a/source/blender/editors/screen/screen_ops.cc
+++ b/source/blender/editors/screen/screen_ops.cc
@@ -4182,9 +4182,10 @@ static void area_join_update_data(bContext *C, sAreaJoinData *jd, const wmEvent
   jd->dock_target = area_docking_target(jd, event);
 
   if (jd->sa1 == area) {
+    const int drag_threshold = 30 * UI_SCALE_FAC;
     jd->sa2 = area;
-    if (!(abs(jd->start_x - event->xy[0]) > (30 * U.pixelsize) ||
-          abs(jd->start_y - event->xy[1]) > (30 * U.pixelsize)))
+    if (!(abs(jd->start_x - event->xy[0]) > drag_threshold ||
+          abs(jd->start_y - event->xy[1]) > drag_threshold))
     {
       /* We haven't moved enough to start a split. */
       jd->dir = SCREEN_DIR_NONE;
diff --git a/source/blender/editors/space_view3d/view3d_draw.cc b/source/blender/editors/space_view3d/view3d_draw.cc
index 25eb3990e75..4df699bb6cb 100644
--- a/source/blender/editors/space_view3d/view3d_draw.cc
+++ b/source/blender/editors/space_view3d/view3d_draw.cc
@@ -959,7 +959,7 @@ float ED_view3d_grid_view_scale(const Scene *scene,
 
 static void draw_view_axis(RegionView3D *rv3d, const rcti *rect)
 {
-  const float k = U.rvisize * U.pixelsize; /* axis size */
+  const float k = U.rvisize * UI_SCALE_FAC; /* axis size */
   /* axis alpha offset (rvibright has range 0-10) */
   const int bright = -20 * (10 - U.rvibright);
 
diff --git a/source/blender/makesdna/DNA_userdef_types.h b/source/blender/makesdna/DNA_userdef_types.h
index 8eab65964f4..39211be29af 100644
--- a/source/blender/makesdna/DNA_userdef_types.h
+++ b/source/blender/makesdna/DNA_userdef_types.h
@@ -876,7 +876,12 @@ typedef struct UserDef {
 
   /** Setting for UI scale (fractional), before screen DPI has been applied. */
   float ui_scale;
-  /** Setting for UI line width. */
+  /**
+   * Setting for UI line width.
+   *
+   * In most cases this should not be used directly it is an offset used to calculate `pixelsize`
+   * which should be used to define the line width.
+   */
   int ui_line_width;
   /** Runtime, full DPI divided by `pixelsize`. */
   int dpi;
@@ -884,7 +889,18 @@ typedef struct UserDef {
   float scale_factor;
   /** Runtime, `1.0 / scale_factor` */
   float inv_scale_factor;
-  /** Runtime, calculated from line-width and point-size based on DPI (rounded to int). */
+  /**
+   * Runtime, calculated from line-width and point-size based on DPI.
+   *
+   * - Rounded down to an integer, clamped to a minimum of 1.0.
+   * - This includes both the UI scale and windowing system's DPI.
+   *   so a HI-DPI display of 200% with a UI scale of 3.0 results in a pixel-size of 6.0
+   *   (when the line-width is set to auto).
+   * - The line-width is added to this value, so lines & vertex drawing can be adjusted.
+   *
+   * \note This should never be used as a UI scale value otherwise changing the line-width
+   * could double or halve the size of UI elements. Use #UI_SCALE_FAC instead.
+   */
   float pixelsize;
   /** Deprecated, for forward compatibility. */
   int virtual_pixel;
diff --git a/source/blender/windowmanager/intern/wm_draw.cc b/source/blender/windowmanager/intern/wm_draw.cc
index 3278068bc12..cc51572801c 100644
--- a/source/blender/windowmanager/intern/wm_draw.cc
+++ b/source/blender/windowmanager/intern/wm_draw.cc
@@ -253,7 +253,7 @@ static void wm_software_cursor_draw_bitmap(const int event_xy[2],
 
   GPU_matrix_push();
 
-  const int scale = int(U.pixelsize);
+  const int scale = std::max(1, round_fl_to_int(UI_SCALE_FAC));
 
   unit_m4(gl_matrix);
 
diff --git a/source/blender/windowmanager/intern/wm_gesture.cc b/source/blender/windowmanager/intern/wm_gesture.cc
index ffe621b214c..97adfbc11be 100644
--- a/source/blender/windowmanager/intern/wm_gesture.cc
+++ b/source/blender/windowmanager/intern/wm_gesture.cc
@@ -138,7 +138,7 @@ static void wm_gesture_draw_line_active_side(const rcti *rect, const bool flip)
   GPU_blend(GPU_BLEND_ALPHA);
   immBindBuiltinProgram(GPU_SHADER_3D_SMOOTH_COLOR);
 
-  const float gradient_length = 150.0f * U.pixelsize;
+  const float gradient_length = 150.0f * UI_SCALE_FAC;
   float line_dir[2];
   float gradient_dir[2];
   float gradient_point[2][2];