diff --git a/libnfc/target-subr.c b/libnfc/target-subr.c
index 97e2882..61cedfd 100644
--- a/libnfc/target-subr.c
+++ b/libnfc/target-subr.c
@@ -503,7 +503,7 @@ snprint_nfc_barcode_info(char *dst, size_t size, const nfc_barcode_info *pnti, b
 {
   (void) verbose;
   int off = 0;
-  off += snprintf(dst + off, size - off, "        Size (bits): %lu\n", pnti->szDataLen * 8);
+  off += snprintf(dst + off, size - off, "        Size (bits): %lu\n", (unsigned long)(pnti->szDataLen * 8));
   off += snprintf(dst + off, size - off, "            Content: ");
   for (uint8_t i = 0; i < pnti->szDataLen; i++) {
     off += snprintf(dst + off, size - off, "%02X", pnti->abtData[i]);
diff --git a/utils/nfc-mfclassic.c b/utils/nfc-mfclassic.c
index bc3fe6c..3f22c61 100644
--- a/utils/nfc-mfclassic.c
+++ b/utils/nfc-mfclassic.c
@@ -695,7 +695,7 @@ main(int argc, const char *argv[])
       magic2 = true;
     }
   }
-  printf("Guessing size: seems to be a %lu-byte card\n", (uiBlocks + 1) * sizeof(mifare_classic_block));
+  printf("Guessing size: seems to be a %lu-byte card\n", (unsigned long)((uiBlocks + 1) * sizeof(mifare_classic_block)));
 
   if (bUseKeyFile) {
     FILE *pfKeys = fopen(argv[5], "rb");
diff --git a/utils/nfc-mfultralight.c b/utils/nfc-mfultralight.c
index 3fe2100..5e71a3a 100644
--- a/utils/nfc-mfultralight.c
+++ b/utils/nfc-mfultralight.c
@@ -714,7 +714,7 @@ main(int argc, const char *argv[])
 
     size_t  szDump;
     if (((szDump = fread(&mtDump, 1, sizeof(mtDump), pfDump)) != iDumpSize && !bPart) || szDump <= 0) {
-      ERR("Could not read from dump file or size mismatch: %s (read %lu, expected %lu)\n", argv[2], szDump, iDumpSize);
+      ERR("Could not read from dump file or size mismatch: %s (read %lu, expected %lu)\n", argv[2], (unsigned long)szDump, (unsigned long)iDumpSize);
       fclose(pfDump);
       exit(EXIT_FAILURE);
     }