The difference between semipermanent and permanent hair color is how long you want the color to last and how much of a change you want.
If you’re looking to subtly deepen your natural hair color or add a layer of color (such as a red tone on brown hair), a semipermanent color is your best option. Keep in mind semipermanents darkenhair. Because they don’t contain ammonia or peroxide, semipermanent color can’t lighten hair.
Semipermanent color washes out over a period of time (six to 12 shampoos, depending upon the formula), so if you don’t like the color you don’t have to live with it for too long. Another benefit of semipermanent color: Because the color is temporary, you won’t have to deal with noticeable roots.
Want a longer-lasting option? Consider a demipermanent color which, like semipermanent color, deepens and intensifies your natural color but won’t lighten hair. The difference is demipermanent color lasts 12-26 washes, depending on the formula.
If you want a more dramatic change (two or more shades darker or lighter than your natural hair color), a permanent coloris a better option.
Permanent hair color contains a blend of peroxide and ammonia and removes pigment from hair while also depositing new color.
Looking to cover gray hairs? Permanent color is the way to go. It won’t wash out and instead has to grow out. You’ll need to re-touch roots every six to eight weeks.