diff --git a/acmed/src/certificate.rs b/acmed/src/certificate.rs
index d1e3f5e..d5ca601 100644
--- a/acmed/src/certificate.rs
+++ b/acmed/src/certificate.rs
@@ -105,7 +105,7 @@ impl Certificate {
 
     fn is_expiring(&self, cert: &X509Certificate) -> Result<bool, Error> {
         let expires_in = cert.expires_in()?;
-        self.debug(&format!("expires in {}s", expires_in.as_secs()));
+        self.debug(&format!("expires in {} days", expires_in.as_secs() / 86400));
         // TODO: allow a custom duration (using time-parse ?)
         // 1814400 is 3 weeks (3 * 7 * 24 * 60 * 60)
         let renewal_time = Duration::new(1814400, 0);