Not too strong, clean fragrance. I’m sensitive to certain smells and this one is not overpowering. We actually like to smell our home fragrance throughout the day. Only concern is that it could be a bit stronger. We have our device running on silent for the bulk of the day at level 6 and will need to replace in about 20 days. Not sure what the optimal settings would be for noticeable fragrance and cartridge best use.