It has a light hum when cooling. Most people wouldn't notice as we are typically surrounded by a 60hz hum, but in a tiny cabin in the still woods its noticeable. Still pretty quiet and not annoying, more like if you pause for a moment when it's running you might wonder where that faint hum is coming from. I dont think I would even notice with background from freeway noise and everything else in my house. If you want silent as possible look for a fridget with thermo electric unit instead of compressor.