There isn't a specific coffee scrub that's best for skin whitening. Coffee scrubs can help exfoliate dead skin cells, leaving skin feeling smoother and brighter. However, coffee scrubs don't lighten skin tone.
If you're looking for a way to brighten your skin, consider using a scrub with ingredients like vitamin C, licorice root extract, or kojic acid which have been shown to help brighten skin tone.
It's important to note that skin whitening can be a sensitive topic and there are ethical considerations surrounding products that claim to lighten skin. It's always best to consult with a dermatologist for personalized advice on skin care.