diff --git a/Arduino.mk b/Arduino.mk
index 5a045066..3a03686c 100644
--- a/Arduino.mk
+++ b/Arduino.mk
@@ -1260,7 +1260,7 @@ else
 endif
 
 LDFLAGS       += -$(MCU_FLAG_NAME)=$(MCU) -Wl,--gc-sections -O$(OPTIMIZATION_LEVEL)
-SIZEFLAGS     ?= --mcu=$(MCU) -C
+SIZEFLAGS     ?= --mcu=$(MCU) --format=avr
 
 # for backwards compatibility, grab ARDUINO_PORT if the user has it set
 # instead of MONITOR_PORT
diff --git a/HISTORY.md b/HISTORY.md
index 5f538a0c..61203343 100644
--- a/HISTORY.md
+++ b/HISTORY.md
@@ -37,6 +37,7 @@ I tried to give credit whenever possible. If I have missed anyone, kindly add it
 - New: Build the ArduinoCore API
 - New: Support for Python 3 and multi-os Python installation using new PYTHON_CMD variable.
 - New: Add "ARDUINO_{build.board}" to be able to detect board type.
+- Fix: Update format flag for `avr-size` command (pull #686)
 
 ### 1.6.0 (2017-07-11)
 - Fix: Allowed for SparkFun's weird usb pid/vid submenu shenanigans (issue #499). (https://github.com/sej7278)