diff --git a/src/PhpSpreadsheet/Comment.php b/src/PhpSpreadsheet/Comment.php
index a4d389749..e2fcd83ed 100644
--- a/src/PhpSpreadsheet/Comment.php
+++ b/src/PhpSpreadsheet/Comment.php
@@ -2,6 +2,7 @@
 
 namespace PhpOffice\PhpSpreadsheet;
 
+use PhpOffice\PhpSpreadsheet\Helper\Size;
 use PhpOffice\PhpSpreadsheet\RichText\RichText;
 use PhpOffice\PhpSpreadsheet\Style\Alignment;
 use PhpOffice\PhpSpreadsheet\Style\Color;
@@ -132,7 +133,10 @@ class Comment implements IComparable
      */
     public function setWidth(string $width): self
     {
-        $this->width = $width;
+        $result = new Size($width);
+        if ($result->valid()) {
+            $this->width = $result->size() . $result->unit();
+        }
 
         return $this;
     }
@@ -150,7 +154,10 @@ class Comment implements IComparable
      */
     public function setHeight(string $height): self
     {
-        $this->height = $height;
+        $result = new Size($height);
+        if ($result->valid()) {
+            $this->height = $result->size() . $result->unit();
+        }
 
         return $this;
     }
@@ -168,7 +175,10 @@ class Comment implements IComparable
      */
     public function setMarginLeft(string $margin): self
     {
-        $this->marginLeft = $margin;
+        $result = new Size($margin);
+        if ($result->valid()) {
+            $this->marginLeft = $result->size() . $result->unit();
+        }
 
         return $this;
     }
@@ -186,7 +196,10 @@ class Comment implements IComparable
      */
     public function setMarginTop(string $margin): self
     {
-        $this->marginTop = $margin;
+        $result = new Size($margin);
+        if ($result->valid()) {
+            $this->marginTop = $result->size() . $result->unit();
+        }
 
         return $this;
     }
diff --git a/src/PhpSpreadsheet/Helper/Size.php b/src/PhpSpreadsheet/Helper/Size.php
new file mode 100644
index 000000000..e1a4d8693
--- /dev/null
+++ b/src/PhpSpreadsheet/Helper/Size.php
@@ -0,0 +1,38 @@
+<?php
+
+namespace PhpOffice\PhpSpreadsheet\Helper;
+
+class Size
+{
+    const REGEXP_SIZE_VALIDATION = '/^(?P<size>\d*\.?\d+)(?P<unit>pt|px|em)?$/i';
+
+    protected $valid;
+
+    protected $size = '';
+
+    protected $unit = '';
+
+    public function __construct(string $size)
+    {
+        $this->valid  = preg_match(self::REGEXP_SIZE_VALIDATION, $size, $matches);
+        if ($this->valid) {
+            $this->size = $matches['size'];
+            $this->unit = $matches['unit'] ?? 'pt';
+        }
+    }
+
+    public function valid(): bool
+    {
+        return $this->valid;
+    }
+
+    public function size()
+    {
+        return $this->size;
+    }
+
+    public function unit()
+    {
+        return $this->unit;
+    }
+}
diff --git a/tests/PhpSpreadsheetTests/CommentTest.php b/tests/PhpSpreadsheetTests/CommentTest.php
index c41267e6e..f21efdf05 100644
--- a/tests/PhpSpreadsheetTests/CommentTest.php
+++ b/tests/PhpSpreadsheetTests/CommentTest.php
@@ -57,8 +57,8 @@ class CommentTest extends TestCase
     public function testSetHeight(): void
     {
         $comment = new Comment();
-        $comment->setHeight('60pt');
-        self::assertEquals('60pt', $comment->getHeight());
+        $comment->setHeight('60px');
+        self::assertEquals('60px', $comment->getHeight());
     }
 
     public function testSetFillColor(): void