diff --git a/Userland/Libraries/LibWeb/CSS/ComputedValues.h b/Userland/Libraries/LibWeb/CSS/ComputedValues.h
index 69d912ef83..ecb9c23134 100644
--- a/Userland/Libraries/LibWeb/CSS/ComputedValues.h
+++ b/Userland/Libraries/LibWeb/CSS/ComputedValues.h
@@ -15,7 +15,7 @@ namespace Web::CSS {
 
 class InitialValues {
 public:
-    static float font_size() { return 10; }
+    static float font_size() { return 16; }
     static int font_weight() { return 400; }
     static CSS::FontVariant font_variant() { return CSS::FontVariant::Normal; }
     static CSS::Float float_() { return CSS::Float::None; }
diff --git a/Userland/Libraries/LibWeb/CSS/Default.css b/Userland/Libraries/LibWeb/CSS/Default.css
index 8319932a48..30ef6d8fde 100644
--- a/Userland/Libraries/LibWeb/CSS/Default.css
+++ b/Userland/Libraries/LibWeb/CSS/Default.css
@@ -11,13 +11,37 @@ body {
     margin: 8px;
 }
 
-h1,
-h2 {
-    font-family: Pebbleton;
-    font-size: 14px;
-    font-weight: bold;
+h1 {
+    font-size: 2em;
+    margin: 0.67em 0;
 }
 
+h2 {
+    font-size: 1.5em;
+    margin: 0.83em 0;
+}
+
+h3 {
+    font-size: 1.17em;
+    margin: 1em 0;
+}
+
+h4 {
+    margin: 1.33em 0;
+}
+
+h5 {
+    font-size: 0.83em;
+    margin: 1.67em 0;
+}
+
+h6 {
+    font-size: 0.67em;
+    margin: 2.33em 0;
+}
+
+h1,
+h2,
 h3,
 h4,
 h5,
diff --git a/Userland/Libraries/LibWeb/CSS/StyleComputer.cpp b/Userland/Libraries/LibWeb/CSS/StyleComputer.cpp
index 7f7a096efa..2e4931b45a 100644
--- a/Userland/Libraries/LibWeb/CSS/StyleComputer.cpp
+++ b/Userland/Libraries/LibWeb/CSS/StyleComputer.cpp
@@ -855,7 +855,7 @@ void StyleComputer::compute_defaulted_values(StyleProperties& style, DOM::Elemen
 
 float StyleComputer::root_element_font_size() const
 {
-    constexpr float default_root_element_font_size = 10;
+    constexpr float default_root_element_font_size = 16;
 
     auto const* root_element = m_document.first_child_of_type<HTML::HTMLHtmlElement>();
     if (!root_element)
@@ -921,7 +921,7 @@ void StyleComputer::compute_font(StyleProperties& style, DOM::Element const* ele
 
     bool bold = weight > Gfx::FontWeight::Regular;
 
-    float font_size_in_px = 10;
+    float font_size_in_px = 16;
 
     if (font_size->is_identifier()) {
         switch (static_cast<IdentifierStyleValue const&>(*font_size).id()) {
@@ -930,7 +930,7 @@ void StyleComputer::compute_font(StyleProperties& style, DOM::Element const* ele
         case CSS::ValueID::Small:
         case CSS::ValueID::Medium:
             // FIXME: Should be based on "user's default font size"
-            font_size_in_px = 10;
+            font_size_in_px = 16;
             break;
         case CSS::ValueID::Large:
         case CSS::ValueID::XLarge: