diff --git a/armsrc/appmain.c b/armsrc/appmain.c
index dfd4f0751..0fdfa6fd1 100644
--- a/armsrc/appmain.c
+++ b/armsrc/appmain.c
@@ -1090,8 +1090,8 @@ static void PacketReceived(PacketCommandNG *packet) {
             em4x50_write((em4x50_data_t *)packet->data.asBytes);
             break;
         }
-        case CMD_LF_EM4X50_WRITE_PASSWORD: {
-            em4x50_write_password((em4x50_data_t *)packet->data.asBytes);
+        case CMD_LF_EM4X50_WRITEPWD: {
+            em4x50_writepwd((em4x50_data_t *)packet->data.asBytes);
             break;
         }
         case CMD_LF_EM4X50_READ: {
@@ -1140,6 +1140,10 @@ static void PacketReceived(PacketCommandNG *packet) {
             emlSet(packet->data.asBytes, packet->oldarg[0], packet->oldarg[1]);
             break;
         }
+        case CMD_LF_EM4X50_CHK: {
+            em4x50_chk((uint32_t *)packet->data.asBytes);
+            break;
+        }
 #endif
 
 #ifdef WITH_ISO15693
diff --git a/armsrc/em4x50.h b/armsrc/em4x50.h
index 57ad94b4d..d1a94d662 100644
--- a/armsrc/em4x50.h
+++ b/armsrc/em4x50.h
@@ -21,7 +21,7 @@ bool em4x50_sim_send_word(uint32_t word);
 
 void em4x50_info(em4x50_data_t *etd);
 void em4x50_write(em4x50_data_t *etd);
-void em4x50_write_password(em4x50_data_t *etd);
+void em4x50_writepwd(em4x50_data_t *etd);
 void em4x50_read(em4x50_data_t *etd);
 void em4x50_wipe(uint32_t *password);
 void em4x50_brute(em4x50_data_t *etd);
@@ -31,5 +31,6 @@ void em4x50_watch(void);
 void em4x50_restore(em4x50_data_t *etd);
 void em4x50_sim(void);
 void em4x50_stdread(void);
+void em4x50_chk(uint32_t *numkeys);
 
 #endif /* EM4X50_H */
diff --git a/client/src/cmdlfem4x.c b/client/src/cmdlfem4x.c
index 8370edcfb..0c038a438 100644
--- a/client/src/cmdlfem4x.c
+++ b/client/src/cmdlfem4x.c
@@ -654,7 +654,7 @@ static command_t CommandTable[] = {
     {"4x50_dump",   CmdEM4x50Dump,        IfPm3EM4x50,     "dump EM4x50 tag"},
     {"4x50_info",   CmdEM4x50Info,        IfPm3EM4x50,     "tag information EM4x50"},
     {"4x50_write",  CmdEM4x50Write,       IfPm3EM4x50,     "write word data to EM4x50"},
-    {"4x50_write_password", CmdEM4x50WritePassword, IfPm3EM4x50, "change password of EM4x50 tag"},
+    {"4x50_writepwd",CmdEM4x50WritePwd,   IfPm3EM4x50,     "change password of EM4x50 tag"},
     {"4x50_read",   CmdEM4x50Read,        IfPm3EM4x50,     "read word data from EM4x50"},
     {"4x50_wipe",   CmdEM4x50Wipe,        IfPm3EM4x50,     "wipe data from EM4x50"},
     {"4x50_brute",  CmdEM4x50Brute,       IfPm3EM4x50,     "guess password of EM4x50"},
@@ -666,6 +666,7 @@ static command_t CommandTable[] = {
     {"4x50_stdread",CmdEM4x50StdRead,     IfPm3EM4x50,     "show standard read mode data of EM4x50 tag"},
     {"4x50_eload",  CmdEM4x50ELoad,       IfPm3EM4x50,     "load a binary dump into emulator memory"},
     {"4x50_esave",  CmdEM4x50ESave,       IfPm3EM4x50,     "save emulator memory to file"},
+    {"4x50_chk",    CmdEM4x50Chk,         IfPm3EM4x50,     "check passwords from dictionary"},
     {NULL, NULL, NULL, NULL}
 };
 
diff --git a/client/src/cmdlfem4x50.h b/client/src/cmdlfem4x50.h
index 2c84d9f15..753210f0a 100644
--- a/client/src/cmdlfem4x50.h
+++ b/client/src/cmdlfem4x50.h
@@ -20,7 +20,7 @@ int em4x50_read(em4x50_data_t *etd, em4x50_word_t *out);
 
 int CmdEM4x50Info(const char *Cmd);
 int CmdEM4x50Write(const char *Cmd);
-int CmdEM4x50WritePassword(const char *Cmd);
+int CmdEM4x50WritePwd(const char *Cmd);
 int CmdEM4x50Read(const char *Cmd);
 int CmdEM4x50Dump(const char *Cmd);
 int CmdEM4x50Wipe(const char *Cmd);
@@ -33,5 +33,6 @@ int CmdEM4x50Sim(const char *Cmd);
 int CmdEM4x50StdRead(const char *Cmd);
 int CmdEM4x50ELoad(const char *Cmd);
 int CmdEM4x50ESave(const char *Cmd);
+int CmdEM4x50Chk(const char *Cmd);
 
 #endif
diff --git a/include/pm3_cmd.h b/include/pm3_cmd.h
index bf05735da..d90b78f60 100644
--- a/include/pm3_cmd.h
+++ b/include/pm3_cmd.h
@@ -505,7 +505,7 @@ typedef struct {
 #define CMD_LF_EM410X_WATCH                                               0x021C
 #define CMD_LF_EM4X50_INFO                                                0x0240
 #define CMD_LF_EM4X50_WRITE                                               0x0241
-#define CMD_LF_EM4X50_WRITE_PASSWORD                                      0x0242
+#define CMD_LF_EM4X50_WRITEPWD                                            0x0242
 #define CMD_LF_EM4X50_READ                                                0x0243
 #define CMD_LF_EM4X50_WIPE                                                0x0244
 #define CMD_LF_EM4X50_BRUTE                                               0x0245
@@ -516,6 +516,7 @@ typedef struct {
 #define CMD_LF_EM4X50_SIM                                                 0x0250
 #define CMD_LF_EM4X50_STDREAD                                             0x0251
 #define CMD_LF_EM4X50_ESET                                                0x0252
+#define CMD_LF_EM4X50_CHK                                                 0x0253
 // Sampling configuration for LF reader/sniffer
 #define CMD_LF_SAMPLING_SET_CONFIG                                        0x021D
 #define CMD_LF_FSK_SIMULATE                                               0x021E