diff --git a/lib/buffer.js b/lib/buffer.js
index ca73549eba..f15de7d8ac 100644
--- a/lib/buffer.js
+++ b/lib/buffer.js
@@ -799,8 +799,8 @@ Buffer.prototype.write = function(string, offset, length, encoding) {
 
 
 Buffer.prototype.toJSON = function() {
-  if (this.length) {
-    const data = [];
+  if (this.length > 0) {
+    const data = new Array(this.length);
     for (var i = 0; i < this.length; ++i)
       data[i] = this[i];
     return { type: 'Buffer', data };