diff --git a/Firmware/Marlin_main.cpp b/Firmware/Marlin_main.cpp
index 06d38a782..493ad68f2 100755
--- a/Firmware/Marlin_main.cpp
+++ b/Firmware/Marlin_main.cpp
@@ -5293,7 +5293,7 @@ if(eSoundMode!=e_SOUND_MODE_SILENT)
   */
 	case 75:
 	{
-		for (int i = 40; i <= 110; i++)
+		for (uint8_t i = 40; i <= 110; i++)
 			printf_P(_N("%d  %.2f"), i, temp_comp_interpolation(i));
 	}
 	break;
@@ -7791,8 +7791,8 @@ Sigma_Exit:
     */
     case 300: // M300
     {
-      int beepS = code_seen('S') ? code_value() : 110;
-      int beepP = code_seen('P') ? code_value() : 1000;
+      uint16_t beepS = code_seen('S') ? code_value() : 110;
+      uint16_t beepP = code_seen('P') ? code_value() : 1000;
       if (beepS > 0)
       {
         #if BEEPER > 0
@@ -11487,8 +11487,8 @@ void restore_print_from_eeprom(bool mbl_was_active) {
 	depth = eeprom_read_byte((uint8_t*)EEPROM_DIR_DEPTH);
 	
 	MYSERIAL.println(int(depth));
-	for (int i = 0; i < depth; i++) {
-		for (int j = 0; j < 8; j++) {
+	for (uint8_t i = 0; i < depth; i++) {
+		for (uint8_t j = 0; j < 8; j++) {
 			dir_name[j] = eeprom_read_byte((uint8_t*)EEPROM_DIRS + j + 8 * i);
 		}
 		dir_name[8] = '\0';
@@ -11497,7 +11497,7 @@ void restore_print_from_eeprom(bool mbl_was_active) {
 		card.chdir(dir_name, false);
 	}
 
-	for (int i = 0; i < 8; i++) {
+	for (uint8_t i = 0; i < 8; i++) {
 		filename[i] = eeprom_read_byte((uint8_t*)EEPROM_FILENAME + i);
 	}
 	filename[8] = '\0';
diff --git a/Firmware/lcd.cpp b/Firmware/lcd.cpp
index 37b70f1a1..024f973f9 100644
--- a/Firmware/lcd.cpp
+++ b/Firmware/lcd.cpp
@@ -344,7 +344,7 @@ void lcd_createChar_P(uint8_t location, const uint8_t* charmap)
 {
   location &= 0x7; // we only have 8 locations 0-7
   lcd_command(LCD_SETCGRAMADDR | (location << 3));
-  for (int i=0; i<8; i++)
+  for (uint8_t i = 0; i < 8; i++)
     lcd_send(pgm_read_byte(&charmap[i]), HIGH);
 }
 
diff --git a/Firmware/mesh_bed_calibration.cpp b/Firmware/mesh_bed_calibration.cpp
index ef83e5735..f97851059 100644
--- a/Firmware/mesh_bed_calibration.cpp
+++ b/Firmware/mesh_bed_calibration.cpp
@@ -2240,7 +2240,7 @@ BedSkewOffsetDetectionResultType find_bed_offset_and_skew(int8_t verbosity_level
     /// Retry point scanning if a point with bad data appears.
     /// Bad data could be cause by "cold" sensor.
     /// This behavior vanishes after few point scans so retry will help.
-    for (int retries = 0; retries <= 1; ++retries) {
+    for (uint8_t retries = 0; retries <= 1; ++retries) {
         bool retry = false;
         for (int k = 0; k < 4; ++k) {
             // Don't let the manage_inactivity() function remove power from the motors.
diff --git a/Firmware/planner.cpp b/Firmware/planner.cpp
index b6d012b24..5c89a5456 100644
--- a/Firmware/planner.cpp
+++ b/Firmware/planner.cpp
@@ -1023,7 +1023,7 @@ Having the real displacement of the head, we can calculate the total movement le
     // Calculate speed in mm/second for each axis. No divide by zero due to previous checks.
   float inverse_second = feed_rate * inverse_millimeters;
 
-  int moves_queued = moves_planned();
+  uint8_t moves_queued = moves_planned();
 
   // slow down when de buffer starts to empty, rather than wait at the corner for a buffer refill
 #ifdef SLOWDOWN
diff --git a/Firmware/tmc2130.cpp b/Firmware/tmc2130.cpp
index dbce5ea07..30712379e 100755
--- a/Firmware/tmc2130.cpp
+++ b/Firmware/tmc2130.cpp
@@ -911,7 +911,7 @@ void tmc2130_set_wave(uint8_t axis, uint8_t amp, uint8_t fac1000)
 	uint8_t s = 0;                 //current segment
 	int8_t b;                      //encoded bit value
     int8_t dA;                     //delta value
-	int i;                         //microstep index
+	uint8_t i;                         //microstep index
 	uint32_t reg = 0;              //tmc2130 register
 	tmc2130_wr_MSLUTSTART(axis, 0, amp);
 	for (i = 0; i < 256; i++)
diff --git a/Firmware/ultralcd.cpp b/Firmware/ultralcd.cpp
index e580eba3e..5ed326a04 100755
--- a/Firmware/ultralcd.cpp
+++ b/Firmware/ultralcd.cpp
@@ -693,7 +693,7 @@ void lcdui_print_status_line(void)
     }
 
     // Fill the rest of line to have nice and clean output
-    for(int fillspace = 0; fillspace < LCD_WIDTH; fillspace++)
+    for(uint8_t fillspace = 0; fillspace < LCD_WIDTH; fillspace++)
         if ((lcd_status_message[fillspace] <= 31 ))
             lcd_print(' ');
 }
@@ -2737,7 +2737,7 @@ void lcd_menu_statistics()
 }
 
 
-static void _lcd_move(const char *name, int axis, int min, int max)
+static void _lcd_move(const char *name, uint8_t axis, int min, int max)
 {
     if (homing_flag || mesh_bed_leveling_flag)
     {
@@ -3920,7 +3920,7 @@ static void prusa_statistics_case0(uint8_t statnr){
 	prusa_stat_printinfo();
 }
 
-void prusa_statistics(int _message, uint8_t _fil_nr) {
+void prusa_statistics(uint8_t _message, uint8_t _fil_nr) {
 #ifdef DEBUG_DISABLE_PRUSA_STATISTICS
 	return;
 #endif //DEBUG_DISABLE_PRUSA_STATISTICS
diff --git a/Firmware/ultralcd.h b/Firmware/ultralcd.h
index 68b933d02..06763556b 100755
--- a/Firmware/ultralcd.h
+++ b/Firmware/ultralcd.h
@@ -41,7 +41,7 @@ void lcd_pause_print();
 void lcd_pause_usb_print();
 void lcd_resume_print();
 void lcd_print_stop();
-void prusa_statistics(int _message, uint8_t _col_nr = 0);
+void prusa_statistics(uint8_t _message, uint8_t _col_nr = 0);
 unsigned char lcd_choose_color();
 void lcd_load_filament_color_check();
 //void lcd_mylang();