diff --git a/armsrc/epa.c b/armsrc/epa.c
index fabeec6d2..7ccb0a8f6 100644
--- a/armsrc/epa.c
+++ b/armsrc/epa.c
@@ -470,14 +470,14 @@ void EPA_PACE_Replay(PacketCommandNG *c) {
     uint8_t response_apdu[300] = {0};
 
     // now replay the data and measure the timings
-    for (int i = 0; i < sizeof(apdu_lengths_replay); i++) {
+    for (int i = 0; i < ARRAYLEN(apdu_lengths_replay); i++) {
         StartCountUS();
         func_return = EPA_APDU(apdus_replay[i].data,
                                apdu_lengths_replay[i],
                                response_apdu);
         timings[i] = GetCountUS();
         // every step but the last one should succeed
-        if (i < sizeof(apdu_lengths_replay) - 1
+        if (i < ARRAYLEN(apdu_lengths_replay) - 1
                 && (func_return < 6
                     || response_apdu[func_return - 4] != 0x90
                     || response_apdu[func_return - 3] != 0x00)) {
diff --git a/armsrc/felica.c b/armsrc/felica.c
index 48b6f4464..5420f56d4 100644
--- a/armsrc/felica.c
+++ b/armsrc/felica.c
@@ -746,7 +746,7 @@ void felica_dump_lite_s() {
             // for (c=0; c < 8; c++)
             // ndef[c] = FelicaFrame.framebytes[c+4];
 
-            for (blknum = 0; blknum < sizeof(liteblks);) {
+            for (blknum = 0; blknum < ARRAYLEN(liteblks);) {
 
                 // block to read.
                 BuildFliteRdblk(ndef, 1, &liteblks[blknum]);
diff --git a/armsrc/mifarecmd.c b/armsrc/mifarecmd.c
index 2d56a8a37..26ab16e03 100644
--- a/armsrc/mifarecmd.c
+++ b/armsrc/mifarecmd.c
@@ -1495,7 +1495,7 @@ OUT:
 
         uint16_t bar = 0;
         uint8_t j = 0;
-        for (uint8_t m = 64; m < sizeof(found); m++) {
+        for (uint8_t m = 64; m < ARRAYLEN(found); m++) {
             bar |= ((uint16_t)(found[m] & 1) << j++);
         }
 
diff --git a/client/cmddata.c b/client/cmddata.c
index 7ade24586..473c5f0b9 100644
--- a/client/cmddata.c
+++ b/client/cmddata.c
@@ -870,7 +870,7 @@ static int CmdBitsamples(const char *Cmd) {
         return PM3_ETIMEOUT;
     }
 
-    for (size_t j = 0; j < sizeof(got); j++) {
+    for (size_t j = 0; j < ARRAYLEN(got); j++) {
         for (uint8_t k = 0; k < 8; k++) {
             if (got[j] & (1 << (7 - k)))
                 GraphBuffer[cnt++] = 1;
diff --git a/client/cmdhfepa.c b/client/cmdhfepa.c
index 9aeaabefd..a2a120764 100644
--- a/client/cmdhfepa.c
+++ b/client/cmdhfepa.c
@@ -75,7 +75,7 @@ static int CmdHFEPAPACEReplay(const char *Cmd) {
 
     int skip = 0, skip_add = 0, scan_return;
     // for each APDU
-    for (int i = 0; i < sizeof(apdu_lengths); i++) {
+    for (int i = 0; i < ARRAYLEN(apdu_lengths); i++) {
         // scan to next space or end of string
         while (Cmd[skip] != ' ' && Cmd[skip] != '\0') {
             // convert
@@ -96,7 +96,7 @@ static int CmdHFEPAPACEReplay(const char *Cmd) {
 
         // break on EOF
         if (Cmd[skip] == '\0') {
-            if (i < sizeof(apdu_lengths) - 1) {
+            if (i < ARRAYLEN(apdu_lengths) - 1) {
 
                 PrintAndLogEx(NORMAL, (char *)usage_msg);
                 return 0;
@@ -111,7 +111,7 @@ static int CmdHFEPAPACEReplay(const char *Cmd) {
     uint8_t data[PM3_CMD_DATA_SIZE];
     // fast push mode
     conn.block_after_ACK = true;
-    for (int i = 0; i < sizeof(apdu_lengths); i++) {
+    for (int i = 0; i < ARRAYLEN(apdu_lengths); i++) {
         // transfer the APDU in several parts if necessary
         for (int j = 0; j * sizeof(data) < apdu_lengths[i]; j++) {
             // amount of data in this packet
@@ -119,7 +119,7 @@ static int CmdHFEPAPACEReplay(const char *Cmd) {
             if (packet_length > sizeof(data)) {
                 packet_length = sizeof(data);
             }
-            if ((i == sizeof(apdu_lengths) - 1) && (j * sizeof(data) >= apdu_lengths[i] - 1)) {
+            if ((i == ARRAYLEN(apdu_lengths) - 1) && (j * sizeof(data) >= apdu_lengths[i] - 1)) {
                 // Disable fast mode on last packet
                 conn.block_after_ACK = false;
             }
diff --git a/client/cmdhficlass.c b/client/cmdhficlass.c
index 91757bbd4..17fd9f127 100644
--- a/client/cmdhficlass.c
+++ b/client/cmdhficlass.c
@@ -1570,7 +1570,7 @@ static void HFiClassCalcNewKey(uint8_t *CSN, uint8_t *OLDKEY, uint8_t *NEWKEY, u
     //get new div key
     HFiClassCalcDivKey(CSN, NEWKEY, new_div_key, elite);
 
-    for (uint8_t i = 0; i < sizeof(old_div_key); i++) {
+    for (uint8_t i = 0; i < ARRAYLEN(old_div_key); i++) {
         xor_div_key[i] = old_div_key[i] ^ new_div_key[i];
     }
     if (verbose) {
diff --git a/client/cmdhfmfp.c b/client/cmdhfmfp.c
index fb1118b81..46ee6e680 100644
--- a/client/cmdhfmfp.c
+++ b/client/cmdhfmfp.c
@@ -227,7 +227,7 @@ static int CmdHFMFPInitPerso(const char *cmd) {
     }
 
     mfpSetVerboseMode(verbose);
-    for (int i = 0; i < sizeof(CardAddresses) / 2; i++) {
+    for (int i = 0; i < ARRAYLEN(CardAddresses); i++) {
         keyNum[0] = CardAddresses[i] >> 8;
         keyNum[1] = CardAddresses[i] & 0xff;
         res = MFPWritePerso(keyNum, key, false, true, data, sizeof(data), &datalen);
diff --git a/client/cmdhfmfu.c b/client/cmdhfmfu.c
index b7d268884..0158d3394 100644
--- a/client/cmdhfmfu.c
+++ b/client/cmdhfmfu.c
@@ -2298,7 +2298,7 @@ static int CmdHF14AMfURestore(const char *Cmd) {
 
         // otp, uid, lock, cfg1, cfg0, dynlockbits
         uint8_t blocks[] = {3, 0, 1, 2, pages - 5, pages - 4, pages - 3};
-        for (uint8_t i = 0; i < sizeof(blocks); i++) {
+        for (uint8_t i = 0; i < ARRAYLEN(blocks); i++) {
             uint8_t b = blocks[i];
             memcpy(data, mem->data + (b * 4), 4);
             clearCommandBuffer();
@@ -2635,12 +2635,12 @@ static int CmdHF14AMfUGenDiverseKeys(const char *Cmd) {
     PrintAndLogEx(NORMAL, "Message      :\t %s", sprint_hex(mix, sizeof(mix)));
     PrintAndLogEx(NORMAL, "Diversified key: %s", sprint_hex(divkey + 1, 6));
 
-    for (int i = 0; i < sizeof(mifarekeyA); ++i) {
+    for (int i = 0; i < ARRAYLEN(mifarekeyA); ++i) {
         dkeyA[i]  = (mifarekeyA[i] << 1) & 0xff;
         dkeyA[6] |= ((mifarekeyA[i] >> 7) & 1) << (i + 1);
     }
 
-    for (int i = 0; i < sizeof(mifarekeyB); ++i) {
+    for (int i = 0; i < ARRAYLEN(mifarekeyB); ++i) {
         dkeyB[1]  |= ((mifarekeyB[i] >> 7) & 1) << (i + 1);
         dkeyB[2 + i] = (mifarekeyB[i] << 1) & 0xff;
     }
diff --git a/client/cmdlfhid.c b/client/cmdlfhid.c
index cc395c8c5..56f9667a3 100644
--- a/client/cmdlfhid.c
+++ b/client/cmdlfhid.c
@@ -485,7 +485,7 @@ static int CmdHIDWiegand(const char *Cmd) {
 
     PrintAndLogEx(NORMAL, "HID | OEM | FC   | CN      |  Wiegand  |  HID Formatted");
     PrintAndLogEx(NORMAL, "----+-----+------+---------+-----------+--------------------");
-    for (uint8_t i = 0; i < sizeof(fmtlen); i++) {
+    for (uint8_t i = 0; i < ARRAYLEN(fmtlen); i++) {
         memset(bits, 0x00, sizeof(bits));
         calcWiegand(fmtlen[i], fc, cardnum, bs, oem);
         PrintAndLogEx(NORMAL, "ice:: %s \n", sprint_bin(bs, fmtlen[i]));
@@ -545,7 +545,7 @@ static int CmdHIDBrute(const char *Cmd) {
                 cmdp += 2;
                 bool is_ftm_ok = false;
                 uint8_t ftms[] = {26, 33, 34, 35, 37};
-                for (uint8_t i = 0; i < sizeof(ftms); i++) {
+                for (uint8_t i = 0; i < ARRAYLEN(ftms); i++) {
                     if (ftms[i] == fmtlen) {
                         is_ftm_ok = true;
                     }
diff --git a/client/cmdsmartcard.c b/client/cmdsmartcard.c
index c49f0d0e7..c2268fd2f 100644
--- a/client/cmdsmartcard.c
+++ b/client/cmdsmartcard.c
@@ -878,7 +878,7 @@ static void smart_brute_prim() {
 
     PrintAndLogEx(INFO, "Reading primitives");
 
-    for (int i = 0; i < sizeof(get_card_data); i += 5) {
+    for (int i = 0; i < ARRAYLEN(get_card_data); i += 5) {
 
         clearCommandBuffer();
         SendCommandOLD(CMD_SMART_RAW, SC_RAW_T0, 5, 0, get_card_data + i, 5);
diff --git a/client/loclass/cipherutils.c b/client/loclass/cipherutils.c
index c829574e9..b6bea6186 100644
--- a/client/loclass/cipherutils.c
+++ b/client/loclass/cipherutils.c
@@ -205,7 +205,7 @@ static int testBitStream() {
     } else {
         PrintAndLogDevice(FAILED, "    Bitstream test 1 failed");
         uint8_t i;
-        for (i = 0 ; i < sizeof(input) ; i++) {
+        for (i = 0 ; i < ARRAYLEN(input) ; i++) {
             PrintAndLogDevice(NORMAL, "    IN %02x, OUT %02x", input[i], output[i]);
         }
         return 1;
@@ -235,7 +235,7 @@ static int testReversedBitstream() {
     } else {
         PrintAndLogDevice(FAILED, "    Bitstream test 2 failed");
         uint8_t i;
-        for (i = 0 ; i < sizeof(input) ; i++) {
+        for (i = 0 ; i < ARRAYLEN(input) ; i++) {
             PrintAndLogDevice(NORMAL, "    IN %02x, MIDDLE: %02x, OUT %02x", input[i], reverse[i], output[i]);
         }
         return 1;
diff --git a/client/loclass/ikeys.c b/client/loclass/ikeys.c
index 70605942f..67278e3b5 100644
--- a/client/loclass/ikeys.c
+++ b/client/loclass/ikeys.c
@@ -692,7 +692,7 @@ int doKeyTests(uint8_t debuglevel) {
         //Test if it's the right key...
         uint8_t i;
         uint8_t j = 0;
-        for (i = 0; i < sizeof(key); i++)
+        for (i = 0; i < ARRAYLEN(key); i++)
             j += key[i];
 
         if (j != 185) {