diff --git a/lib/letter-avatars.js b/lib/letter-avatars.js
index 349e95b9..1ef671a9 100644
--- a/lib/letter-avatars.js
+++ b/lib/letter-avatars.js
@@ -32,9 +32,9 @@ exports.generateAvatarURL = function (name, email = '', big = true) {
   }
   name = encodeURIComponent(name)
 
-  let hash = crypto.createHash('md5')
+  const hash = crypto.createHash('md5')
   hash.update(email.toLowerCase())
-  let hexDigest = hash.digest('hex')
+  const hexDigest = hash.digest('hex')
 
   if (email !== '' && config.allowGravatar) {
     photo = 'https://www.gravatar.com/avatar/' + hexDigest