diff --git a/lib/csr.js b/lib/csr.js
index dea9bf2..219ab27 100644
--- a/lib/csr.js
+++ b/lib/csr.js
@@ -14,10 +14,7 @@ var CSR = module.exports = function rsacsr(opts) {
   opts = CSR._prepare(opts);
 
   return CSR.create(opts).then(function (bytes) {
-    return PEM.packBlock({
-      type: "CERTIFICATE REQUEST"
-    , bytes: bytes /* { jwk: jwk, domains: opts.domains } */
-    });
+    return CSR._encode(opts, bytes);
   });
 };
 
@@ -75,6 +72,12 @@ CSR._prepare = function (opts) {
 CSR.sync = function (opts) {
   opts = CSR._prepare(opts);
   var bytes = CSR.createSync(opts);
+  return CSR._encode(opts, bytes);
+};
+CSR._encode = function (opts, bytes) {
+  if ('der' === (opts.encoding||'').toLowerCase()) {
+    return bytes;
+  }
   return PEM.packBlock({
     type: "CERTIFICATE REQUEST"
   , bytes: bytes /* { jwk: jwk, domains: opts.domains } */