diff --git a/py/pfenv.c b/py/pfenv.c
index 310ca07aa45eb9c1fc04028e1c65a415ee1c4636..92c40184154704ddaefed227f100c3ceedf36096 100644
--- a/py/pfenv.c
+++ b/py/pfenv.c
@@ -29,6 +29,7 @@ int pfenv_print_strn(const pfenv_t *pfenv, const char *str, unsigned int len, in
     int right_pad = 0;
     int pad = width - len;
     int pad_size;
+    int total_chars_printed = 0;
     const char *pad_chars;
 
     if (!fill || fill == ' ' ) {
@@ -53,7 +54,8 @@ int pfenv_print_strn(const pfenv_t *pfenv, const char *str, unsigned int len, in
         left_pad = pad;
     }
 
-    if (left_pad) {
+    if (left_pad > 0) {
+        total_chars_printed += left_pad;
         while (left_pad > 0) {
             int p = left_pad;
             if (p > pad_size) {
@@ -64,7 +66,9 @@ int pfenv_print_strn(const pfenv_t *pfenv, const char *str, unsigned int len, in
         }
     }
     pfenv->print_strn(pfenv->data, str, len);
-    if (right_pad) {
+    total_chars_printed += len;
+    if (right_pad > 0) {
+        total_chars_printed += right_pad;
         while (right_pad > 0) {
             int p = right_pad;
             if (p > pad_size) {
@@ -74,7 +78,7 @@ int pfenv_print_strn(const pfenv_t *pfenv, const char *str, unsigned int len, in
             right_pad -= p;
         }
     }
-    return len;
+    return total_chars_printed;
 }
 
 // 32-bits is 10 digits, add 3 for commas, 1 for sign, 1 for terminating null
diff --git a/stmhal/printf.c b/stmhal/printf.c
index b1eace28de0d06a5951902c1999cf54b0d8e35be..ea90f498031a5e16ce420b527780afea2715bede 100644
--- a/stmhal/printf.c
+++ b/stmhal/printf.c
@@ -244,7 +244,7 @@ void strn_print_strn(void *data, const char *str, unsigned int len) {
     strn_pfenv->cur += len;
     strn_pfenv->remain -= len;
 }
-    
+
 int vsnprintf(char *str, size_t size, const char *fmt, va_list ap) {
     strn_pfenv_t strn_pfenv;
     strn_pfenv.cur = str;