erinb It DOES work on blonde - So I have some natural dark hair underneath plus well grown roots into my light blond hair. It stuck to all of it but obviously more so the light blonde versus the darker blonde natural color. Took me A LOT of washes to get it out but that’s what I wanted. It’s inexpensive and worth a shot. It didn’t get as hot hot pink as I wanted so I combined it with a hot pink one I picked up from Target too so you’ll see some hot pink parts to my hair and some lighter parts which were this product