Olaplex No. 9 Nourishing Hair Serum
Seeing dull hair, tangles, or poor style retention? These could be signs of pollution or heat damage. Protect your hair from daily damage with this weightless, leave-in, silicone-free hair serum to shield hair from pollution for 48 hours and provide heat protection up to 450°F (232°C).
With antioxidant-rich Red Algae Extract and scientifically proven OLAPLEX® Bond Building Technology™.
Key Benefits
- Shields hair from pollution for up to 48 hours
- Provides heat protection up to 450°F (232°C)
- Free from silicones
- Lightweight, leave-in formula
| Feature | Detail |
|---|---|
| Active Ingredients | Red Algae Extract, OLAPLEX® Bond Building Technology™ |
| Formulation Type | Leave-in, silicone-free serum |
| Heat Protection | Up to 450°F (232°C) |
| Pollution Protection | 48 hours |
FAQ
How long does the pollution protection last?
The pollution protection lasts for 48 hours when applied as a leave-in serum.
Does this serum provide heat protection?
Yes, it provides heat protection up to 450°F (232°C).
Is the serum suitable for all hair types?
The serum is designed for all hair types and is lightweight, making it ideal for daily use.

Jane Fraser –
My hair has been dull and frizzy since moving to a city with high pollution. After using the Olaplex No. 9 serum regularly, my hair feels smoother and looks brighter. It doesn’t weigh down my strands and helps reduce frizz after styling. I’ve noticed less tangling and better hold on my styles.
Julia Robertson –
I use this serum before blow-drying and styling. It gives me good heat protection and keeps my hair from getting damaged. The scent is mild and the texture is easy to apply. My hair feels more resilient after daily wear.
Austin Alsop –
I’ve tried several hair serums, but this one stands out. The red algae extract seems to nourish my hair while protecting it from environmental damage. I apply it after washing and before styling. My hair looks healthier and feels stronger.
Carol Hamilton –
It’s a great addition to my routine. I use it every day, especially in the city. My hair stays manageable and doesn’t get frizzy easily. The heat protection is reliable when I use a flat iron.
Anna Graham –
After using this serum for a few weeks, my hair has improved significantly. It’s shinier, less damaged, and holds styles better. I appreciate the absence of silicones and the natural ingredients.