diff --git a/index.js b/index.js
index e5be002..975fe67 100644
--- a/index.js
+++ b/index.js
@@ -108,6 +108,10 @@ export function format(css, { minify = false } = {}) {
 
 		children.forEach((child) => {
 			switch (child.type) {
+				case 'TypeSelector': {
+					buffer += lowercase(child.name)
+					break
+				}
 				case 'Combinator': {
 					// putting spaces around `child.name` (+ > ~ or ' '), unless the combinator is ' '
 					buffer += SPACE
diff --git a/test/selectors.test.js b/test/selectors.test.js
index 52c6570..7cbb7f2 100644
--- a/test/selectors.test.js
+++ b/test/selectors.test.js
@@ -56,6 +56,18 @@ a > b ~ c d,
 	assert.equal(actual, expected)
 })
 
+test('lowercases type selectors', () => {
+	let actual = format(`
+		A,
+		B,
+		C {}
+	`)
+	let expected = `a,
+b,
+c {}`
+	assert.equal(actual, expected)
+})
+
 test('formats nested selector combinators', () => {
 	let fixtures = [
 		[`:where(a+b) {}`, `:where(a + b) {}`],