diff --git a/src/openpgp.js b/src/openpgp.js
index 02f69e2a..50167cd4 100644
--- a/src/openpgp.js
+++ b/src/openpgp.js
@@ -391,7 +391,7 @@ function formatUserIds(options) {
     if (!util.isString(id.name) || (id.email && !util.isEmailAddress(id.email))) {
       throw new Error('Invalid user id format');
     }
-    if (id.name) {
+    if (id.name.length > 0) {
       id.name += ' ';
     }
     return id.name + '<' + id.email + '>';