diff --git a/src/printbox-md/PrintBox_md.ml b/src/printbox-md/PrintBox_md.ml
index 14ebc06..a953cfe 100644
--- a/src/printbox-md/PrintBox_md.ml
+++ b/src/printbox-md/PrintBox_md.ml
@@ -290,10 +290,11 @@ let pp c out b =
           rows)
     | B.Grid (_, [||]) -> ()
     | B.Grid (bars, rows) when bars <> `None && is_native_table c rows ->
+      let n_rows = Array.length rows and n_cols = Array.length rows.(0) in
       let lengths =
         Array.fold_left (Array.map2 (fun len b -> max len @@ line_of_length_heuristic_exn c b))
-          (Array.map (fun _ -> 0) rows.(0)) rows in
-      let n_rows = Array.length rows and n_cols = Array.length rows.(0) in
+          (Array.map (fun b -> line_of_length_heuristic_exn c b - 4) rows.(0))
+          @@ Array.sub rows 1 (n_rows - 1) in
       Array.iteri (fun i header ->
           let header = remove_bold header in
           loop ~no_block:true ~no_md ~prefix:"" header;
diff --git a/src/printbox-md/README.md b/src/printbox-md/README.md
index f4db709..fb0b222 100644
--- a/src/printbox-md/README.md
+++ b/src/printbox-md/README.md
@@ -136,10 +136,10 @@ Trees are rendered as:
 
 There is a special case carved out for Markdown syntax tables.
 
-Header    |cells    |[must be]    |bold.
-----------|---------|-------------|-----------------
-Rows      |[must be]|single       |line.
-[Only]    |then     |**we get**   |a Markdown table.
+Header|cells    |[must be] |bold.
+------|---------|----------|-----------------
+Rows  |[must be]|single    |line.
+[Only]|then     |**we get**|a Markdown table.
 
 <div>
  <table class="framed">
diff --git a/test/test_md.expected b/test/test_md.expected
index 936177c..8b0302e 100644
--- a/test/test_md.expected
+++ b/test/test_md.expected
@@ -61,14 +61,14 @@ Test default:
   > > 
   > > 
   > > 
-- header 1    |header 2    |[header 3]
-  ------------|------------|--------------
-  cell 1.1    |[cell 1.2]  |cell 1.3
-  [cell 2.1]  |cell 2.2    |**cell 2.3**
-- > header 1    |header 2    |[header 3]
-  > ------------|------------|--------------
-  > cell 1.1    |[cell 1.2]  |cell 1.3
-  > [cell 2.1]  |cell 2.2    |**cell 2.3**
+- header 1  |header 2  |[header 3]
+  ----------|----------|------------
+  cell 1.1  |[cell 1.2]|cell 1.3
+  [cell 2.1]|cell 2.2  |**cell 2.3**
+- > header 1  |header 2  |[header 3]
+  > ----------|----------|------------
+  > cell 1.1  |[cell 1.2]|cell 1.3
+  > [cell 2.1]|cell 2.2  |**cell 2.3**
 
 Test uniform unfolded:
 
@@ -262,14 +262,14 @@ Test foldable:
   > > 
   > > 
   > > 
-- header 1    |header 2    |[header 3]
-  ------------|------------|--------------
-  cell 1.1    |[cell 1.2]  |cell 1.3
-  [cell 2.1]  |cell 2.2    |**cell 2.3**
-- > header 1    |header 2    |[header 3]
-  > ------------|------------|--------------
-  > cell 1.1    |[cell 1.2]  |cell 1.3
-  > [cell 2.1]  |cell 2.2    |**cell 2.3**
+- header 1  |header 2  |[header 3]
+  ----------|----------|------------
+  cell 1.1  |[cell 1.2]|cell 1.3
+  [cell 2.1]|cell 2.2  |**cell 2.3**
+- > header 1  |header 2  |[header 3]
+  > ----------|----------|------------
+  > cell 1.1  |[cell 1.2]|cell 1.3
+  > [cell 2.1]|cell 2.2  |**cell 2.3**
 </details>
 
 
diff --git a/test/test_md.expected.md b/test/test_md.expected.md
index 936177c..8b0302e 100644
--- a/test/test_md.expected.md
+++ b/test/test_md.expected.md
@@ -61,14 +61,14 @@ Test default:
   > > 
   > > 
   > > 
-- header 1    |header 2    |[header 3]
-  ------------|------------|--------------
-  cell 1.1    |[cell 1.2]  |cell 1.3
-  [cell 2.1]  |cell 2.2    |**cell 2.3**
-- > header 1    |header 2    |[header 3]
-  > ------------|------------|--------------
-  > cell 1.1    |[cell 1.2]  |cell 1.3
-  > [cell 2.1]  |cell 2.2    |**cell 2.3**
+- header 1  |header 2  |[header 3]
+  ----------|----------|------------
+  cell 1.1  |[cell 1.2]|cell 1.3
+  [cell 2.1]|cell 2.2  |**cell 2.3**
+- > header 1  |header 2  |[header 3]
+  > ----------|----------|------------
+  > cell 1.1  |[cell 1.2]|cell 1.3
+  > [cell 2.1]|cell 2.2  |**cell 2.3**
 
 Test uniform unfolded:
 
@@ -262,14 +262,14 @@ Test foldable:
   > > 
   > > 
   > > 
-- header 1    |header 2    |[header 3]
-  ------------|------------|--------------
-  cell 1.1    |[cell 1.2]  |cell 1.3
-  [cell 2.1]  |cell 2.2    |**cell 2.3**
-- > header 1    |header 2    |[header 3]
-  > ------------|------------|--------------
-  > cell 1.1    |[cell 1.2]  |cell 1.3
-  > [cell 2.1]  |cell 2.2    |**cell 2.3**
+- header 1  |header 2  |[header 3]
+  ----------|----------|------------
+  cell 1.1  |[cell 1.2]|cell 1.3
+  [cell 2.1]|cell 2.2  |**cell 2.3**
+- > header 1  |header 2  |[header 3]
+  > ----------|----------|------------
+  > cell 1.1  |[cell 1.2]|cell 1.3
+  > [cell 2.1]|cell 2.2  |**cell 2.3**
 </details>