diff --git a/lib/certificates.js b/lib/certificates.js
index 5e18e9d49..c18b9f37b 100644
--- a/lib/certificates.js
+++ b/lib/certificates.js
@@ -141,7 +141,11 @@ export async function createCertificate ( { domains, maxAge, commonName, ...attr
 
     return {
         "certificate": `-----BEGIN CERTIFICATE-----
-${ certificate.toString( "base64" ) }
+${ certificate
+    .toString( "base64" )
+    .split( /(.{64})/ )
+    .filter( line => line )
+    .join( "\n" ) }
 -----END CERTIFICATE-----
 `,
         "privateKey": crypto.KeyObject.from( keyPair.privateKey ).export( {