diff --git a/lib/privatekey.js b/lib/privatekey.js
index 0fd2ed5..948e3a5 100644
--- a/lib/privatekey.js
+++ b/lib/privatekey.js
@@ -189,7 +189,7 @@ PrivateKey.fromWIF = function(str) {
  * @returns {PrivateKey} A new valid instance of PrivateKey
  */
 PrivateKey.fromJSON = function(json) {
-  if (JSUtil.isValidJson(json)) {
+  if (JSUtil.isValidJSON(json)) {
     json = JSON.parse(json);
   }
   var bn = BN(json.bn, 'hex');
diff --git a/lib/publickey.js b/lib/publickey.js
index c556e7a..d9fbc2b 100644
--- a/lib/publickey.js
+++ b/lib/publickey.js
@@ -162,7 +162,7 @@ PublicKey._transformX = function(odd, x){
  * @returns {PublicKey} A new valid instance of PublicKey
  */
 PublicKey.fromJSON = function(json) {
-  if (JSUtil.isValidJson(json)) {
+  if (JSUtil.isValidJSON(json)) {
     json = JSON.parse(json);
   }
   var x = BN(json.x, 'hex');