diff --git a/mod/memory b/mod/memory
index 40db576..d249eb1 100644
--- a/mod/memory
+++ b/mod/memory
@@ -9,17 +9,17 @@ class ModMemory < Worker
 				mem[k] = v.to_i
 			end
 
-			avail_part = mem["MemAvailable:"]/(mem["MemTotal:"]/100)
+			used_part = 100 - (mem["MemAvailable:"]/(mem["MemTotal:"]/100))
 
-			if avail_part < @my_config['crit_value']
+			if used_part < @my_config['crit_value']
 				fg_colour = @my_config['crit_colour']
-			elsif avail_part < @my_config['warn_value']
+			elsif used_part < @my_config['warn_value']
 				fg_colour = @my_config['warn_colour']
 			else
 				fg_colour = @my_config['ok_colour']
 			end
 
-			self.write "%%{F%s}%s%%{F-}" % [ fg_colour, avail_part.to_s ]
+			self.write "%%{F%s}%s%%{F-}" % [ fg_colour, used_part.to_s ]
 
 			sleep(1)
 		end