Quiet Portable Air Coolers: How to Compare Noise and Modes

That depends on the fan speed and your sensitivity to sound. Check the manufacturer’s noise figure for the sleep or night setting, if published, rather than relying on the word ‘quiet’ in a product title.

It is a manufacturer-listed sound level, but its usefulness depends on distance, speed and test conditions. Compare like-for-like measurements and remember that a higher fan setting can sound different from the rated setting.

No. Night mode usually changes fan behaviour or timing; it does not imply silent operation. Check whether the maker publishes a separate noise level for that mode.

There is no universal answer. Both types use fans, and air conditioners can also have compressor noise; compare independent measurements for the exact models and operating settings.