diff --git a/src/containers/TimeConverter.tsx b/src/containers/TimeConverter.tsx
index 1f558bc..55f74f4 100644
--- a/src/containers/TimeConverter.tsx
+++ b/src/containers/TimeConverter.tsx
@@ -17,7 +17,12 @@ export function TimeConverter() {
           type="checkbox"
           data-testid="use-system-time"
           checked={useSystemTime}
-          onChange={(e) => setUseSystemTime(e.target.checked)}
+          onChange={(e) => {
+            setUseSystemTime(e.target.checked);
+            if (e.target.checked) {
+              setCurrentTime(new Date());
+            }
+          }}
         />
         Use system time
       </label>