diff --git a/src/ascii.rs b/src/ascii.rs
index 8940733..b5e9e44 100644
--- a/src/ascii.rs
+++ b/src/ascii.rs
@@ -127,6 +127,7 @@ impl<S: AsRef<str>> Hash for Ascii<S> {
         for byte in self.as_ref().bytes().map(|b| b.to_ascii_lowercase()) {
             hasher.write_u8(byte);
         }
+        hasher.write_u8(0xff);
     }
 }
 
diff --git a/src/unicode/mod.rs b/src/unicode/mod.rs
index 8b88733..3a03503 100644
--- a/src/unicode/mod.rs
+++ b/src/unicode/mod.rs
@@ -59,8 +59,9 @@ impl<S: AsRef<str>> Hash for Unicode<S> {
         let mut buf = [0; 4];
         for c in self.0.as_ref().chars().flat_map(|c| lookup(c)) {
             let len = char_to_utf8(c, &mut buf);
-            hasher.write(&buf[..len])
+            hasher.write(&buf[..len]);
         }
+        hasher.write_u8(0xff);
     }
 }