diff --git a/Libraries/LibHTML/HtmlView.cpp b/Libraries/LibHTML/HtmlView.cpp
index a8948f8f18..b77b547f6e 100644
--- a/Libraries/LibHTML/HtmlView.cpp
+++ b/Libraries/LibHTML/HtmlView.cpp
@@ -64,7 +64,6 @@ void HtmlView::set_document(Document* new_document)
         };
     }
 
-
 #ifdef HTML_DEBUG
     if (document != nullptr) {
         dbgprintf("\033[33;1mLayout tree before layout:\033[0m\n");
@@ -159,6 +158,11 @@ void HtmlView::mousemove_event(GMouseEvent& event)
                 is_hovering_link = true;
             }
         }
+        if (m_in_mouse_selection) {
+            layout_root()->selection().set_end({ result.layout_node, result.index_in_node });
+            dump_selection("MouseMove");
+            update();
+        }
     }
     if (window())
         window()->set_override_cursor(is_hovering_link ? GStandardCursor::Hand : GStandardCursor::None);
@@ -196,6 +200,12 @@ void HtmlView::mousedown_event(GMouseEvent& event)
                 dbg() << "HtmlView: clicking on a link to " << link->href();
                 if (on_link_click)
                     on_link_click(link->href());
+            } else {
+                if (event.button() == GMouseButton::Left) {
+                    layout_root()->selection().set({ result.layout_node, result.index_in_node }, {});
+                    dump_selection("MouseDown");
+                    m_in_mouse_selection = true;
+                }
             }
         }
     }
@@ -204,6 +214,17 @@ void HtmlView::mousedown_event(GMouseEvent& event)
     event.accept();
 }
 
+void HtmlView::mouseup_event(GMouseEvent& event)
+{
+    if (!layout_root())
+        return GScrollableWidget::mouseup_event(event);
+
+    if (event.button() == GMouseButton::Left) {
+        dump_selection("MouseUp");
+        m_in_mouse_selection = false;
+    }
+}
+
 void HtmlView::keydown_event(GKeyEvent& event)
 {
     if (event.modifiers() == 0) {
@@ -352,3 +373,10 @@ const Document* HtmlView::document() const
 {
     return main_frame().document();
 }
+
+void HtmlView::dump_selection(const char* event_name)
+{
+    dbg() << event_name << " selection start: "
+          << layout_root()->selection().start().layout_node << ":" << layout_root()->selection().start().index_in_node << ", end: "
+          << layout_root()->selection().end().layout_node << ":" << layout_root()->selection().end().index_in_node;
+}
diff --git a/Libraries/LibHTML/HtmlView.h b/Libraries/LibHTML/HtmlView.h
index 189133a79e..ea2b8b733e 100644
--- a/Libraries/LibHTML/HtmlView.h
+++ b/Libraries/LibHTML/HtmlView.h
@@ -43,12 +43,15 @@ protected:
     virtual void paint_event(GPaintEvent&) override;
     virtual void mousemove_event(GMouseEvent&) override;
     virtual void mousedown_event(GMouseEvent&) override;
+    virtual void mouseup_event(GMouseEvent&) override;
     virtual void keydown_event(GKeyEvent&) override;
 
 private:
     void layout_and_sync_size();
+    void dump_selection(const char* event_name);
 
     RefPtr<Frame> m_main_frame;
 
     bool m_should_show_line_box_borders { false };
+    bool m_in_mouse_selection { false };
 };
diff --git a/Libraries/LibHTML/Layout/LayoutBlock.cpp b/Libraries/LibHTML/Layout/LayoutBlock.cpp
index 3ba37a9088..f5cb6f3935 100644
--- a/Libraries/LibHTML/Layout/LayoutBlock.cpp
+++ b/Libraries/LibHTML/Layout/LayoutBlock.cpp
@@ -293,7 +293,7 @@ HitTestResult LayoutBlock::hit_test(const Point& position) const
     for (auto& line_box : m_line_boxes) {
         for (auto& fragment : line_box.fragments()) {
             if (enclosing_int_rect(fragment.rect()).contains(position)) {
-                return { fragment.layout_node() };
+                return { fragment.layout_node(), fragment.text_index_at(position.x()) };
             }
         }
     }
diff --git a/Libraries/LibHTML/Layout/LayoutDocument.h b/Libraries/LibHTML/Layout/LayoutDocument.h
index ec1ce9d276..18b44c21be 100644
--- a/Libraries/LibHTML/Layout/LayoutDocument.h
+++ b/Libraries/LibHTML/Layout/LayoutDocument.h
@@ -12,5 +12,9 @@ public:
     virtual const char* class_name() const override { return "LayoutDocument"; }
     virtual void layout() override;
 
+    const LayoutRange& selection() const { return m_selection; }
+    LayoutRange& selection() { return m_selection; }
+
 private:
+    LayoutRange m_selection;
 };
diff --git a/Libraries/LibHTML/Layout/LayoutNode.h b/Libraries/LibHTML/Layout/LayoutNode.h
index ad504df269..f4e2181068 100644
--- a/Libraries/LibHTML/Layout/LayoutNode.h
+++ b/Libraries/LibHTML/Layout/LayoutNode.h
@@ -5,6 +5,7 @@
 #include <LibDraw/Rect.h>
 #include <LibHTML/CSS/StyleProperties.h>
 #include <LibHTML/Layout/BoxModelMetrics.h>
+#include <LibHTML/Layout/LayoutPosition.h>
 #include <LibHTML/RenderingContext.h>
 #include <LibHTML/TreeNode.h>
 
@@ -19,6 +20,7 @@ class Node;
 
 struct HitTestResult {
     RefPtr<LayoutNode> layout_node;
+    int index_in_node { 0 };
 };
 
 class LayoutNode : public TreeNode<LayoutNode> {
diff --git a/Libraries/LibHTML/Layout/LayoutPosition.h b/Libraries/LibHTML/Layout/LayoutPosition.h
new file mode 100644
index 0000000000..30fac23368
--- /dev/null
+++ b/Libraries/LibHTML/Layout/LayoutPosition.h
@@ -0,0 +1,56 @@
+#pragma once
+
+#include <AK/RefPtr.h>
+
+class LayoutNode;
+
+struct LayoutPosition {
+    bool operator>=(const LayoutPosition& other) const
+    {
+        if (layout_node == other.layout_node)
+            return index_in_node >= other.index_in_node;
+
+        // FIXME: Implement.
+        return true;
+    }
+
+    bool operator<=(const LayoutPosition& other) const
+    {
+        if (layout_node == other.layout_node)
+            return index_in_node <= other.index_in_node;
+
+        // FIXME: Implement.
+        return false;
+    }
+
+    RefPtr<LayoutNode> layout_node;
+    int index_in_node { 0 };
+};
+
+class LayoutRange {
+public:
+    LayoutRange() {}
+    LayoutRange(const LayoutPosition& start, const LayoutPosition& end)
+        : m_start(start)
+        , m_end(end)
+    {
+    }
+
+    bool is_valid() const { return m_start.layout_node && m_end.layout_node; }
+
+    void set(const LayoutPosition& start, const LayoutPosition& end)
+    {
+        m_start = start;
+        m_end = end;
+    }
+
+    void set_start(const LayoutPosition& start) { m_start = start; }
+    void set_end(const LayoutPosition& end) { m_end = end; }
+
+    const LayoutPosition& start() const { return m_start; }
+    const LayoutPosition& end() const { return m_end; }
+
+private:
+    LayoutPosition m_start;
+    LayoutPosition m_end;
+};
diff --git a/Libraries/LibHTML/Layout/LineBoxFragment.cpp b/Libraries/LibHTML/Layout/LineBoxFragment.cpp
index c987483b2b..40c88e1764 100644
--- a/Libraries/LibHTML/Layout/LineBoxFragment.cpp
+++ b/Libraries/LibHTML/Layout/LineBoxFragment.cpp
@@ -1,4 +1,5 @@
 #include <LibGUI/GPainter.h>
+#include <LibHTML/Layout/LayoutDocument.h>
 #include <LibHTML/Layout/LayoutText.h>
 #include <LibHTML/Layout/LineBoxFragment.h>
 #include <LibHTML/RenderingContext.h>
@@ -26,3 +27,24 @@ StringView LineBoxFragment::text() const
         return {};
     return to<LayoutText>(layout_node()).node().data().substring_view(m_start, m_length);
 }
+
+int LineBoxFragment::text_index_at(float x) const
+{
+    if (!layout_node().is_text())
+        return 0;
+    auto& layout_text = to<LayoutText>(layout_node());
+    auto& font = layout_text.style().font();
+    Utf8View view(text());
+
+    float relative_x = x - m_rect.location().x();
+    float glyph_spacing = font.glyph_spacing();
+
+    float width_so_far = 0;
+    for (auto it = view.begin(); it != view.end(); ++it) {
+        float glyph_width = font.glyph_or_emoji_width(*it);
+        if ((width_so_far + glyph_width + glyph_spacing) > relative_x)
+            return m_start + view.byte_offset_of(it);
+        width_so_far += glyph_width + glyph_spacing;
+    }
+    return m_start + m_length - 1;
+}
diff --git a/Libraries/LibHTML/Layout/LineBoxFragment.h b/Libraries/LibHTML/Layout/LineBoxFragment.h
index 0b12cce81f..565f960f9e 100644
--- a/Libraries/LibHTML/Layout/LineBoxFragment.h
+++ b/Libraries/LibHTML/Layout/LineBoxFragment.h
@@ -29,6 +29,8 @@ public:
     bool is_justifiable_whitespace() const;
     StringView text() const;
 
+    int text_index_at(float x) const;
+
 private:
     const LayoutNode& m_layout_node;
     int m_start { 0 };