diff --git a/app/components/bulma/subtitle_component.rb b/app/components/bulma/subtitle_component.rb
index d67aace..ab2dbf3 100644
--- a/app/components/bulma/subtitle_component.rb
+++ b/app/components/bulma/subtitle_component.rb
@@ -2,12 +2,13 @@
 
 module Bulma
   class SubtitleComponent < Component
-    def initialize(text = nil)
+    def initialize(text = nil, size: nil)
       @text = text
+      @size = size
     end
 
     def call
-      content_tag :p, @text || content, class: "subtitle"
+      content_tag :p, @text || content, class: class_names("subtitle", "is-#{@size}" => @size.present?)
     end
   end
 end
diff --git a/spec/components/bulma/subtitle_component_spec.rb b/spec/components/bulma/subtitle_component_spec.rb
index bab57ef..bc2552a 100644
--- a/spec/components/bulma/subtitle_component_spec.rb
+++ b/spec/components/bulma/subtitle_component_spec.rb
@@ -18,4 +18,10 @@
 
     expect(page).to have_content "Subtitle"
   end
+
+  it "allows to specify size as option" do
+    render_inline(described_class.new(size: 5))
+
+    expect(page).to have_css "p.is-5"
+  end
 end