diff --git a/armsrc/mifareutil.c b/armsrc/mifareutil.c
index f6e65609c..601f4fc69 100644
--- a/armsrc/mifareutil.c
+++ b/armsrc/mifareutil.c
@@ -183,20 +183,22 @@ int mifare_classic_authex_cmd(struct Crypto1State *pcs, uint32_t uid, uint8_t bl
     uint32_t nr32 = nr[0] << 24 | nr[1] << 16 | nr[2] << 8 | nr[3];
     if (g_dbglevel >= DBG_EXTENDED) {
         if (!isNested) {
-            Dbprintf("auth        cmd: %02x %02x | uid: %08x | nr: %08x %s| nt: %08x %s| par: %i%i%i%i %s",
+            Dbprintf("auth        cmd: %02x %02x | uid: %08x | nr: %08x %s| nt: %08x %s %5i| par: %i%i%i%i %s",
             cmd, blockNo, uid,
             nr32, validate_prng_nonce(nr32) ? "@" : " ",
-            nt, validate_prng_nonce(nt) ? "@" : " ",
+            nt, validate_prng_nonce(nt) ? "@idx" : " idx",
+            validate_prng_nonce(nt) ? nonce16_index(nt >> 16) : -1,
             (receivedAnswerPar[0] >> 7) & 1,
             (receivedAnswerPar[0] >> 6) & 1,
             (receivedAnswerPar[0] >> 5) & 1,
             (receivedAnswerPar[0] >> 4) & 1,
             validate_parity_nonce(nt, receivedAnswerPar[0], nt) ? "ok " : "bad");
         } else {
-            Dbprintf("auth nested cmd: %02x %02x | uid: %08x | nr: %08x %s| nt: %08x %s| par: %i%i%i%i %s| ntenc: %08x %s| parerr: %i%i%i%i",
+            Dbprintf("auth nested cmd: %02x %02x | uid: %08x | nr: %08x %s| nt: %08x %s %5i| par: %i%i%i%i %s| ntenc: %08x %s| parerr: %i%i%i%i",
             cmd, blockNo, uid,
             nr32, validate_prng_nonce(nr32) ? "@" : " ",
-            nt, validate_prng_nonce(nt) ? "@" : " ",
+            nt, validate_prng_nonce(nt) ? "@idx" : " idx",
+            validate_prng_nonce(nt) ? nonce16_index(nt >> 16) : -1,
             (receivedAnswerPar[0] >> 7) & 1,
             (receivedAnswerPar[0] >> 6) & 1,
             (receivedAnswerPar[0] >> 5) & 1,
@@ -947,13 +949,9 @@ bool validate_parity_nonce(uint32_t ntenc, uint8_t ntparenc, uint32_t nt) {
            (((ntpar >> 1) & 1) == oddparity8((nt>>8) & 0xFF));
 }
 
-int nonce_distance(uint32_t from, uint32_t to) {
-    if (!validate_prng_nonce(from) || !validate_prng_nonce(to))
-        return -1;
-    if (from == to)
+int nonce16_distance(uint16_t x, uint16_t y) {
+    if (x == y)
         return 0;
-    uint16_t x = from;
-    uint16_t y = to;
     x = (x & 0xff) << 8 | x >> 8;
     y = (y & 0xff) << 8 | y >> 8;
     uint16_t i = 1;
@@ -965,3 +963,13 @@ int nonce_distance(uint32_t from, uint32_t to) {
     // never reached
     return -1;
 }
+
+int nonce_distance(uint32_t from, uint32_t to) {
+    if (!validate_prng_nonce(from) || !validate_prng_nonce(to))
+        return -1;
+    return nonce16_distance(from >> 16, to >> 16);
+}
+
+int nonce16_index(uint16_t nt) {
+    return nonce16_distance(0x0100, nt) + 1;
+}
diff --git a/armsrc/mifareutil.h b/armsrc/mifareutil.h
index c34206af0..fb4da4543 100644
--- a/armsrc/mifareutil.h
+++ b/armsrc/mifareutil.h
@@ -125,4 +125,6 @@ bool emlCheckValBl(int blockNum);
 bool validate_prng_nonce(uint32_t nonce);
 bool validate_parity_nonce(uint32_t ntenc, uint8_t ntparenc, uint32_t nt);
 int nonce_distance(uint32_t from, uint32_t to);
+int nonce16_distance(uint16_t x, uint16_t y);
+int nonce16_index(uint16_t nt);
 #endif
diff --git a/client/src/cmdhflist.c b/client/src/cmdhflist.c
index f3b4bad50..0d78d1441 100644
--- a/client/src/cmdhflist.c
+++ b/client/src/cmdhflist.c
@@ -2068,7 +2068,7 @@ void annotateMifare(char *exp, size_t size, uint8_t *cmd, uint8_t cmdsize,
                     AuthData.nt = bytes_to_num(cmd, 4);
                     AuthData.nt_enc_par = 0;
                     if (validate_prng_nonce(AuthData.nt)) {
-                        snprintf(exp, size, "AUTH: nt (lfsr16 index %i)", nonce_distance(0x0100, AuthData.nt));
+                        snprintf(exp, size, "AUTH: nt (lfsr16 index %i)", nonce_distance(0, AuthData.nt));
                     } else {
                         snprintf(exp, size, "AUTH: nt");
                     }
diff --git a/client/src/mifare/mifarehost.c b/client/src/mifare/mifarehost.c
index f742e9d81..02496d806 100644
--- a/client/src/mifare/mifarehost.c
+++ b/client/src/mifare/mifarehost.c
@@ -1450,7 +1450,7 @@ int detect_classic_static_encrypted_nonce_ex(uint8_t block_no, uint8_t key_type,
                 (ntencpar >> 3) & 1, (ntencpar >> 2) & 1, (ntencpar >> 1) & 1,
                 ks, nt,
                 oddparity8((nt>>24) & 0xFF), oddparity8((nt>>16) & 0xFF), oddparity8((nt>>8) & 0xFF), oddparity8(nt & 0xFF), 
-                nonce_distance(0x0100, nt));
+                nonce_distance(0, nt));
             } else {
                 PrintAndLogEx(INFO, "nTenc " _GREEN_("%08x") " par {" _YELLOW_("%i%i%i%i") "}=" _YELLOW_("%i%i%ix") " | ks "  _YELLOW_("%08x") " | nT " _YELLOW_("%08x") " par " _YELLOW_("%i%i%i%i") " | " _RED_("not lfsr16") " (wrong key)",
                 ntenc,