diff --git a/src/timer.rs b/src/timer.rs
index c8226fa..af2ca46 100644
--- a/src/timer.rs
+++ b/src/timer.rs
@@ -34,7 +34,7 @@ impl Timer {
 
     /// Returns `true` if this [`Timer`] has expired
     pub fn is_expired(&self) -> bool {
-        let expired = Instant::now() - self.start > self.duration;
+        let expired = self.remaining().is_zero();
         if expired {
             self.handle_expiration()
         };