diff --git a/src/keys.js b/src/keys.js
index f4ad20d..431bbc8 100644
--- a/src/keys.js
+++ b/src/keys.js
@@ -27,7 +27,7 @@ const mergeOptions = require('merge-options')
 const fetchHKP = (identifier, keyserverBaseUrl) => {
   return new Promise(async (resolve, reject) => {
     keyserverBaseUrl = keyserverBaseUrl
-      ? keyserverBaseUrl
+      ? `https://${keyserverBaseUrl}/`
       : 'https://keys.openpgp.org/'
 
     const hkp = new openpgp.HKP(keyserverBaseUrl)