diff --git a/examples/layout/main.go b/examples/layout/main.go
index 21d3b7d4..79c2aa2f 100644
--- a/examples/layout/main.go
+++ b/examples/layout/main.go
@@ -126,9 +126,9 @@ var (
 	list = lipgloss.NewStyle().
 		Border(lipgloss.NormalBorder(), false, true, false, false).
 		BorderForeground(subtle).
-		MarginRight(2).
+		MarginRight(1).
 		Height(8).
-		Width(columnWidth + 1)
+		Width(width / 3)
 
 	listHeader = base.
 			BorderStyle(lipgloss.NormalBorder()).
@@ -152,7 +152,6 @@ var (
 	}
 
 	// Paragraphs/History.
-
 	historyStyle = lipgloss.NewStyle().
 			Align(lipgloss.Left).
 			Foreground(lipgloss.Color("#FAFAFA")).
@@ -282,7 +281,7 @@ func main() {
 				listItem("Pomelo"),
 			),
 		),
-		list.Width(columnWidth).Render(
+		list.Render(
 			lipgloss.JoinVertical(lipgloss.Left,
 				listHeader("Actual Lip Gloss Vendors"),
 				listItem("Glossier"),
@@ -294,7 +293,7 @@ func main() {
 		),
 	)
 
-	doc.WriteString(lipgloss.JoinHorizontal(lipgloss.Top, lists, colors))
+	doc.WriteString(lipgloss.JoinHorizontal(lipgloss.Top, lists, lipgloss.NewStyle().MarginLeft(1).Render(colors)))
 
 	// Marmalade history
 	{
diff --git a/style.go b/style.go
index 0eb5c016..4d0dcf18 100644
--- a/style.go
+++ b/style.go
@@ -267,6 +267,9 @@ func (s Style) Render(strs ...string) string {
 		bottomPadding = s.getAsInt(paddingBottomKey)
 		leftPadding   = s.getAsInt(paddingLeftKey)
 
+		horizontalBorderSize = s.GetHorizontalBorderSize()
+		verticalBorderSize   = s.GetVerticalBorderSize()
+
 		colorWhitespace = s.getAsBool(colorWhitespaceKey, true)
 		inline          = s.getAsBool(inlineKey, false)
 		maxWidth        = s.getAsInt(maxWidthKey)
@@ -361,6 +364,10 @@ func (s Style) Render(strs ...string) string {
 		str = strings.ReplaceAll(str, "\n", "")
 	}
 
+	// Include borders in block size.
+	width -= horizontalBorderSize
+	height -= verticalBorderSize
+
 	// Word wrap
 	if !inline && width > 0 {
 		wrapAt := width - leftPadding - rightPadding
diff --git a/style_test.go b/style_test.go
index 0db740b4..50b73f43 100644
--- a/style_test.go
+++ b/style_test.go
@@ -590,3 +590,53 @@ func TestCarriageReturnInRender(t *testing.T) {
 		t.Fatalf("got(string):\n%s\nwant(string):\n%s", got, want)
 	}
 }
+
+func TestWidth(t *testing.T) {
+	tests := []struct {
+		name  string
+		style Style
+	}{
+		{"width with borders", NewStyle().Padding(0, 2).Border(NormalBorder(), true)},
+		{"width no borders", NewStyle().Padding(0, 2)},
+		{"width unset borders", NewStyle().Padding(0, 2).Border(NormalBorder(), true).BorderLeft(false).BorderRight(false)},
+		{"width single-sided border", NewStyle().Padding(0, 2).Border(NormalBorder(), true).UnsetBorderBottom().UnsetBorderTop().UnsetBorderRight()},
+	}
+	{
+		for _, tc := range tests {
+			t.Run(tc.name, func(t *testing.T) {
+				content := "The Romans learned from the Greeks that quinces slowly cooked with honey would “set” when cool. The Apicius gives a recipe for preserving whole quinces, stems and leaves attached, in a bath of honey diluted with defrutum: Roman marmalade. Preserves of quince and lemon appear (along with rose, apple, plum and pear) in the Book of ceremonies of the Byzantine Emperor Constantine VII Porphyrogennetos."
+				contentWidth := 80 - tc.style.GetHorizontalFrameSize()
+				rendered := tc.style.Width(contentWidth).Render(content)
+				if Width(rendered) != contentWidth {
+					t.Log("\n" + rendered)
+					t.Fatalf("got: %d\n, want: %d", Width(rendered), contentWidth)
+				}
+			})
+		}
+	}
+}
+
+func TestHeight(t *testing.T) {
+	tests := []struct {
+		name  string
+		style Style
+	}{
+		{"height with borders", NewStyle().Width(80).Padding(0, 2).Border(NormalBorder(), true)},
+		{"height no borders", NewStyle().Width(80).Padding(0, 2)},
+		{"height unset borders", NewStyle().Width(80).Padding(0, 2).Border(NormalBorder(), true).BorderBottom(false).BorderTop(false)},
+		{"height single-sided border", NewStyle().Width(80).Padding(0, 2).Border(NormalBorder(), true).UnsetBorderLeft().UnsetBorderBottom().UnsetBorderRight()},
+	}
+	{
+		for _, tc := range tests {
+			t.Run(tc.name, func(t *testing.T) {
+				content := "The Romans learned from the Greeks that quinces slowly cooked with honey would “set” when cool. The Apicius gives a recipe for preserving whole quinces, stems and leaves attached, in a bath of honey diluted with defrutum: Roman marmalade. Preserves of quince and lemon appear (along with rose, apple, plum and pear) in the Book of ceremonies of the Byzantine Emperor Constantine VII Porphyrogennetos."
+				contentHeight := 20 - tc.style.GetVerticalFrameSize()
+				rendered := tc.style.Height(contentHeight).Render(content)
+				if Height(rendered) != contentHeight {
+					t.Log("\n" + rendered)
+					t.Fatalf("got: %d\n, want: %d", Height(rendered), contentHeight)
+				}
+			})
+		}
+	}
+}