Noisli - Noisli is a fantastic background noise and color generator for working and relaxing. Online soothing ambient sounds like White noise, Rain and Coffee Shop.
zenmix.io - Ambient background sound generator
ASMR Hunt - Find what relaxes you the most
Studiowave - Chillout tunes and inspiration
Defonic - Create a unique sound environment at home or in the office
SoundDrown - Ambient sounds to help you focus, relax, and escape