diff --git a/Libraries/LibWeb/HTML/HTMLTableCellElement.cpp b/Libraries/LibWeb/HTML/HTMLTableCellElement.cpp
index b866d784691..392b52d20bb 100644
--- a/Libraries/LibWeb/HTML/HTMLTableCellElement.cpp
+++ b/Libraries/LibWeb/HTML/HTMLTableCellElement.cpp
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2020-2022, Andreas Kling <andreas@ladybird.org>
+ * Copyright (c) 2020-2025, Andreas Kling <andreas@ladybird.org>
  * Copyright (c) 2024, Jamie Mansfield <jmansfield@cadixdev.org>
  *
  * SPDX-License-Identifier: BSD-2-Clause
@@ -99,11 +99,11 @@ void HTMLTableCellElement::apply_presentational_hints(GC::Ref<CSS::CascadedPrope
     if (!table_element)
         return;
 
-    if (auto padding = table_element->padding()) {
-        cascaded_properties->set_property_from_presentational_hint(CSS::PropertyID::PaddingTop, CSS::LengthStyleValue::create(CSS::Length::make_px(padding)));
-        cascaded_properties->set_property_from_presentational_hint(CSS::PropertyID::PaddingBottom, CSS::LengthStyleValue::create(CSS::Length::make_px(padding)));
-        cascaded_properties->set_property_from_presentational_hint(CSS::PropertyID::PaddingLeft, CSS::LengthStyleValue::create(CSS::Length::make_px(padding)));
-        cascaded_properties->set_property_from_presentational_hint(CSS::PropertyID::PaddingRight, CSS::LengthStyleValue::create(CSS::Length::make_px(padding)));
+    if (auto padding = table_element->cellpadding(); padding.has_value()) {
+        cascaded_properties->set_property_from_presentational_hint(CSS::PropertyID::PaddingTop, CSS::LengthStyleValue::create(CSS::Length::make_px(*padding)));
+        cascaded_properties->set_property_from_presentational_hint(CSS::PropertyID::PaddingBottom, CSS::LengthStyleValue::create(CSS::Length::make_px(*padding)));
+        cascaded_properties->set_property_from_presentational_hint(CSS::PropertyID::PaddingLeft, CSS::LengthStyleValue::create(CSS::Length::make_px(*padding)));
+        cascaded_properties->set_property_from_presentational_hint(CSS::PropertyID::PaddingRight, CSS::LengthStyleValue::create(CSS::Length::make_px(*padding)));
     }
 
     auto border = table_element->border();
diff --git a/Libraries/LibWeb/HTML/HTMLTableCellElement.h b/Libraries/LibWeb/HTML/HTMLTableCellElement.h
index 8ff23b8751e..e1645788bd9 100644
--- a/Libraries/LibWeb/HTML/HTMLTableCellElement.h
+++ b/Libraries/LibWeb/HTML/HTMLTableCellElement.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2020, Andreas Kling <andreas@ladybird.org>
+ * Copyright (c) 2020-2025, Andreas Kling <andreas@ladybird.org>
  *
  * SPDX-License-Identifier: BSD-2-Clause
  */
diff --git a/Libraries/LibWeb/HTML/HTMLTableElement.cpp b/Libraries/LibWeb/HTML/HTMLTableElement.cpp
index fd8201267c7..7dd0343d813 100644
--- a/Libraries/LibWeb/HTML/HTMLTableElement.cpp
+++ b/Libraries/LibWeb/HTML/HTMLTableElement.cpp
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2020, Andreas Kling <andreas@ladybird.org>
+ * Copyright (c) 2020-2025, Andreas Kling <andreas@ladybird.org>
  * Copyright (c) 2021, Adam Hodgen <ant1441@gmail.com>
  *
  * SPDX-License-Identifier: BSD-2-Clause
@@ -16,6 +16,7 @@
 #include <LibWeb/DOM/Document.h>
 #include <LibWeb/DOM/ElementFactory.h>
 #include <LibWeb/DOM/HTMLCollection.h>
+#include <LibWeb/HTML/HTMLTableCellElement.h>
 #include <LibWeb/HTML/HTMLTableColElement.h>
 #include <LibWeb/HTML/HTMLTableElement.h>
 #include <LibWeb/HTML/HTMLTableRowElement.h>
@@ -145,11 +146,20 @@ void HTMLTableElement::attribute_changed(FlyString const& name, Optional<String>
     Base::attribute_changed(name, old_value, value, namespace_);
 
     if (name == HTML::AttributeNames::cellpadding) {
+        auto old_cellpadding = m_cellpadding;
         if (value.has_value())
-            m_padding = max(0, parse_integer(value.value()).value_or(0));
+            m_cellpadding = max(0, parse_integer(value.value()).value_or(0));
         else
-            m_padding = 1;
+            m_cellpadding = 1;
 
+        // NOTE: cellpadding is magical, it applies to the cells inside this table, not the table itself.
+        //       When it changes, we need new style for the cells.
+        if (old_cellpadding != m_cellpadding) {
+            for_each_in_subtree_of_type<HTMLTableCellElement>([&](auto& cell) {
+                cell.set_needs_style_update(true);
+                return TraversalDecision::Continue;
+            });
+        }
         return;
     }
 }
@@ -478,9 +488,9 @@ unsigned int HTMLTableElement::border() const
     return parse_border(get_attribute_value(HTML::AttributeNames::border));
 }
 
-unsigned int HTMLTableElement::padding() const
+Optional<u32> HTMLTableElement::cellpadding() const
 {
-    return m_padding;
+    return m_cellpadding;
 }
 
 }
diff --git a/Libraries/LibWeb/HTML/HTMLTableElement.h b/Libraries/LibWeb/HTML/HTMLTableElement.h
index b5926d1b7d8..69c6f9baef4 100644
--- a/Libraries/LibWeb/HTML/HTMLTableElement.h
+++ b/Libraries/LibWeb/HTML/HTMLTableElement.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2020, Andreas Kling <andreas@ladybird.org>
+ * Copyright (c) 2020-2025, Andreas Kling <andreas@ladybird.org>
  *
  * SPDX-License-Identifier: BSD-2-Clause
  */
@@ -48,7 +48,7 @@ public:
     virtual Optional<ARIA::Role> default_role() const override { return ARIA::Role::table; }
 
     unsigned border() const;
-    unsigned padding() const;
+    [[nodiscard]] Optional<u32> cellpadding() const;
 
 private:
     HTMLTableElement(DOM::Document&, DOM::QualifiedName);
@@ -64,7 +64,7 @@ private:
 
     GC::Ptr<DOM::HTMLCollection> mutable m_rows;
     GC::Ptr<DOM::HTMLCollection> mutable m_t_bodies;
-    unsigned m_padding { 1 };
+    Optional<u32> m_cellpadding;
 };
 
 }
diff --git a/Tests/LibWeb/Text/expected/HTML/table-cellpadding.txt b/Tests/LibWeb/Text/expected/HTML/table-cellpadding.txt
new file mode 100644
index 00000000000..58b32d70771
--- /dev/null
+++ b/Tests/LibWeb/Text/expected/HTML/table-cellpadding.txt
@@ -0,0 +1,4 @@
+1px
+5px
+0px
+0px
diff --git a/Tests/LibWeb/Text/input/HTML/table-cellpadding.html b/Tests/LibWeb/Text/input/HTML/table-cellpadding.html
new file mode 100644
index 00000000000..3e3a0d15bd7
--- /dev/null
+++ b/Tests/LibWeb/Text/input/HTML/table-cellpadding.html
@@ -0,0 +1,15 @@
+<script src="../include.js"></script>
+<table id="table"><td id="td"></td></table>
+<script>
+    function testCellpadding(value) {
+        table.setAttribute("cellpadding", value);
+        println(getComputedStyle(td).padding);
+    }
+
+    test(() => {
+        testCellpadding("1");
+        testCellpadding("5");
+        testCellpadding("0");
+        testCellpadding("-1");
+    });
+</script>