diff --git a/Libraries/LibWeb/Layout/GridFormattingContext.cpp b/Libraries/LibWeb/Layout/GridFormattingContext.cpp
index b66ce42b1b0..dd7c38c2154 100644
--- a/Libraries/LibWeb/Layout/GridFormattingContext.cpp
+++ b/Libraries/LibWeb/Layout/GridFormattingContext.cpp
@@ -1937,11 +1937,14 @@ CSSPixelRect GridFormattingContext::get_grid_area_rect(GridItem const& grid_item
         // is that of the corresponding padding edge of the grid container (the padding edge of the scrollable area, if the grid container
         // overflows). These lines become the first and last lines (0th and -0th) of the augmented grid used for positioning absolutely-positioned items.
         CSSPixels height = 0;
-        for (auto const& row_track : m_grid_rows_and_gaps) {
-            height += row_track.base_size;
+        if (m_available_space->height.is_definite()) {
+            height = m_available_space->height.to_px_or_zero();
+        } else {
+            for (auto const& row_track : m_grid_rows_and_gaps)
+                height += row_track.base_size;
         }
-        height += m_grid_container_used_values.padding_top;
-        height += m_grid_container_used_values.padding_bottom;
+        height += m_grid_container_used_values.padding_top + m_grid_container_used_values.padding_bottom;
+
         area_rect.set_height(height);
         area_rect.set_y(-m_grid_container_used_values.padding_top);
     }
@@ -1954,11 +1957,14 @@ CSSPixelRect GridFormattingContext::get_grid_area_rect(GridItem const& grid_item
         }
     } else {
         CSSPixels width = 0;
-        for (auto const& col_track : m_grid_columns_and_gaps) {
-            width += col_track.base_size;
+        if (m_available_space->width.is_definite()) {
+            width = m_available_space->width.to_px_or_zero();
+        } else {
+            for (auto const& col_track : m_grid_columns_and_gaps)
+                width += col_track.base_size;
         }
-        width += m_grid_container_used_values.padding_left;
-        width += m_grid_container_used_values.padding_right;
+        width += m_grid_container_used_values.padding_left + m_grid_container_used_values.padding_right;
+
         area_rect.set_width(width);
         area_rect.set_x(-m_grid_container_used_values.padding_left);
     }
diff --git a/Tests/LibWeb/Text/expected/wpt-import/css/css-grid/abspos/absolute-positioning-grid-container-parent-001.txt b/Tests/LibWeb/Text/expected/wpt-import/css/css-grid/abspos/absolute-positioning-grid-container-parent-001.txt
index 59b57e30ff4..3175066e166 100644
--- a/Tests/LibWeb/Text/expected/wpt-import/css/css-grid/abspos/absolute-positioning-grid-container-parent-001.txt
+++ b/Tests/LibWeb/Text/expected/wpt-import/css/css-grid/abspos/absolute-positioning-grid-container-parent-001.txt
@@ -2,17 +2,17 @@ Harness status: OK
 
 Found 12 tests
 
-3 Pass
-9 Fail
+5 Pass
+7 Fail
 Pass	.container 1
 Pass	.container 2
 Pass	.container 3
-Fail	.container 4
+Pass	.container 4
 Fail	.container 5
 Fail	.container 6
 Fail	.container 7
 Fail	.container 8
 Fail	.container 9
-Fail	.container 10
+Pass	.container 10
 Fail	.container 11
 Fail	.container 12
\ No newline at end of file