diff --git a/dlls/uxtheme/system.c b/dlls/uxtheme/system.c
index 05b86e40b1a..c7ae319da28 100644
--- a/dlls/uxtheme/system.c
+++ b/dlls/uxtheme/system.c
@@ -663,7 +663,7 @@ HTHEME WINAPI OpenThemeDataEx(HWND hwnd, LPCWSTR pszClassList, DWORD flags)
 
     dpi = GetDpiForWindow(hwnd);
     if (!dpi)
-        dpi = 96;
+        dpi = GetDpiForSystem();
 
     return open_theme_data(hwnd, pszClassList, flags, dpi);
 }
diff --git a/dlls/uxtheme/tests/system.c b/dlls/uxtheme/tests/system.c
index 65387561544..22762ecd4a9 100644
--- a/dlls/uxtheme/tests/system.c
+++ b/dlls/uxtheme/tests/system.c
@@ -1122,12 +1122,10 @@ static void test_GetThemePartSize(void)
 
     hr = GetThemePartSize(htheme, hdc, BP_CHECKBOX, CBS_CHECKEDNORMAL, NULL, TS_DRAW, &size);
     ok(hr == S_OK, "GetThemePartSize failed, hr %#lx.\n", hr);
-    todo_wine_if(target_dpi != 96)
     ok(compare_uint(size.cx, expected, 1) && compare_uint(size.cy, expected, 1),
        "Got unexpected size %ldx%ld.\n", size.cx, size.cy);
     hr = GetThemePartSize(htheme, NULL, BP_CHECKBOX, CBS_CHECKEDNORMAL, NULL, TS_DRAW, &size);
     ok(hr == S_OK, "GetThemePartSize failed, hr %#lx.\n", hr);
-    todo_wine_if(target_dpi != 96)
     ok(compare_uint(size.cx, expected, 1) && compare_uint(size.cy, expected, 1),
        "Got unexpected size %ldx%ld.\n", size.cx, size.cy);
     CloseThemeData(htheme);
@@ -1145,12 +1143,10 @@ static void test_GetThemePartSize(void)
     htheme = OpenThemeData(NULL, WC_BUTTONW);
     hr = GetThemePartSize(htheme, hdc, BP_CHECKBOX, CBS_CHECKEDNORMAL, NULL, TS_DRAW, &size);
     ok(hr == S_OK, "GetThemePartSize failed, hr %#lx.\n", hr);
-    todo_wine_if(target_dpi != 96)
     ok(compare_uint(size.cx, expected, 1) && compare_uint(size.cy, expected, 1),
        "Got unexpected size %ldx%ld.\n", size.cx, size.cy);
     hr = GetThemePartSize(htheme, NULL, BP_CHECKBOX, CBS_CHECKEDNORMAL, NULL, TS_DRAW, &size);
     ok(hr == S_OK, "GetThemePartSize failed, hr %#lx.\n", hr);
-    todo_wine_if(target_dpi != 96)
     ok(compare_uint(size.cx, expected, 1) && compare_uint(size.cy, expected, 1),
        "Got unexpected size %ldx%ld.\n", size.cx, size.cy);
     CloseThemeData(htheme);