diff --git a/src/utils.test.ts b/src/utils.test.ts
new file mode 100644
index 0000000..5a4ea33
--- /dev/null
+++ b/src/utils.test.ts
@@ -0,0 +1,15 @@
+import { convertSizeToBytes } from './utils'
+
+describe('utils', () => {
+    it.each`
+        initialSize | expectedSize
+        ${'1 B'}    | ${1}
+        ${'1 kB'}   | ${1000}
+        ${'1 mB'}   | ${1000000}
+    `(
+        'converts sizes properly ($initialSize -> $expectedSize)',
+        ({ initialSize, expectedSize }) => {
+            expect(convertSizeToBytes(initialSize)).toEqual(expectedSize)
+        },
+    )
+})