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CHRONOLOGISTE OVERNIGHT YOUTH SERUM
Overnight Youth Serum by Kérastase is a night treatment infused with Pro-Xylane™ and Ochrophyta Algae, designed to reverse the visible signs of ageing during nighttime.
CHRONOLOGISTE OVERNIGHT YOUTH SERUM is rated
4.8 out of
5 by
28.
Overnight Youth Serum by Kérastase is a night treatment infused with Pro-Xylane™ and Ochrophyta Algae, designed to reverse the visible signs of ageing during nighttime.
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HAIR DIAGNOSTIC
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Description + Benefits + How To
YOUTH REVITALISING CARE
Overnight Youth Serum by Kérastase is a night treatment infused with Pro-Xylane™ and Ochrophyta Algae, designed to reverse the visible signs of ageing during nighttime.
Targeting dryness, dullness, frizz, lack of volume and thickness, this leave-in serum delivers intensive overnight care. Just one pump to deliver powerful actives deep into the hair.
Powered by Pro-Xylane™, a molecule known for its anti-ageing action, and Ochrophyta Algae, the fastest growing algae in the world, a bio-sourced deep sea treasure that captures the regenerative power of the ocean.
Its transformative quick-break texture melds instantly into the hair's lengths, leaving a flawless finish and enveloping hair with the signature Chronologiste fragrance that turns routine care into a luxurious ritual.
HAIR BENEFITS AFTER 1 NIGHT Up to 66% less frizz* Up to 32% more shine* Up to 92% less breakage* 77% say their hair feels revitalised**
*Instrumental test after 1 use of Overnight Youth Serum **Consumer test after one application of full Chronologiste routine, bain+masque+Overnight Youth Serum
BENEFITS
Nourishes Hair
Shiny Hair
Luxurious Care
YOUTH REVITALISING CARE
HELPS REVERSE 5 SIGNS OF HAIR AGEING IN 1 NIGHT* WAKE UP TO FULLER, HEALTHIER LOOKING, SMOOTHER HAIR**
*Instrumental test after application of serum on dryness, dullness, lack of volume, thickness & frizz.
**Consumer test after application of bain + mask + Sérum Nuit Jeunesse, 90 consumers
YOUTH REVITALISING CARE
Overnight Youth Serum by Kérastase is a night treatment infused with Pro-Xylane™ and Ochrophyta Algae, designed to reverse the visible signs of ageing during nighttime.
Targeting dryness, dullness, frizz, lack of volume and thickness, this leave-in serum delivers intensive overnight care. Just one pump to deliver powerful actives deep into the hair.
Powered by Pro-Xylane™, a molecule known for its anti-ageing action, and Ochrophyta Algae, the fastest growing algae in the world, a bio-sourced deep sea treasure that captures the regenerative power of the ocean.
Its transformative quick-break texture melds instantly into the hair's lengths, leaving a flawless finish and enveloping hair with the signature Chronologiste fragrance that turns routine care into a luxurious ritual.
HAIR BENEFITS AFTER 1 NIGHT Up to 66% less frizz* Up to 32% more shine* Up to 92% less breakage* 77% say their hair feels revitalised**
*Instrumental test after 1 use of Overnight Youth Serum **Consumer test after one application of full Chronologiste routine, bain+masque+Overnight Youth Serum
BENEFITS
Nourishes Hair
Shiny Hair
Luxurious Care
YOUTH REVITALISING CARE
HELPS REVERSE 5 SIGNS OF HAIR AGEING IN 1 NIGHT* WAKE UP TO FULLER, HEALTHIER LOOKING, SMOOTHER HAIR**
*Instrumental test after application of serum on dryness, dullness, lack of volume, thickness & frizz.
**Consumer test after application of bain + mask + Sérum Nuit Jeunesse, 90 consumers
Step 1: Apply on dry or damp hair before bedtime.
Step 2: Spread one pump into hands and distribute on lengths and ends.
Step 3: No need to rinse in the morning.
In case of direct contact with eyes, rinse immediately and thoroughly.
B/A PRODUCT CAROUSEL
BEFORE / AFTER
Illustration of the contemplated results obtained after applying:
Its transformative quick-break texture melds instantly into the hair's lengths, leaving a flawless finish and enveloping hair with the signature Chronologiste fragrance that turns routine care into a luxurious ritual.
Powered by Pro-Xylane™, a molecule known for its anti-ageing action, and Ochrophyta Algae, the fastest growing algae in the world, a bio-sourced deep sea treasure that captures the regenerative power of the ocean.
Pro-Xylane™ is a molecule from chemistry, known for reinforcing fibre structure and increasing hair thickness.
Ochrophyta Algae is a bio-sourced marine extract rich in regenerative minerals, protecting hair against daily agressors and providing deep revitalisation.
KEY INGREDIENTS
Pro-Xylane™ A molecule from green chemistry, known for reinforcing fibre structure and increasing hair thickness.
Ochrophyta Algae A bio-sourced marine extract rich in regenerative minerals, protecting hair against daily agressors and providing deep revitalisation.
AQUA / WATER / EAU
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• C13-14 ISOALKANE
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• CARVONE
• CITRUS AURANTIUM PEEL OIL
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• POGOSTEMON CABLIN OIL
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• LINALYL ACETATE
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• MACROCYSTIS PYRIFERA EXTRACT / KELP EXTRACT
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• BENZALDEHYDE
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• TRIMETHYLBENZENEPROPANOL
• ROSE KETONES
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• BETA-CARYOPHYLLENE
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CAVIAR OF LONGEVITY
Its transformative quick-break texture melds instantly into the hair's lengths, leaving a flawless finish and enveloping hair with the signature Chronologiste fragrance that turns routine care into a luxurious ritual.
Powered by Pro-Xylane™, a molecule known for its anti-ageing action, and Ochrophyta Algae, the fastest growing algae in the world, a bio-sourced deep sea treasure that captures the regenerative power of the ocean.
Pro-Xylane™ is a molecule from chemistry, known for reinforcing fibre structure and increasing hair thickness.
Ochrophyta Algae is a bio-sourced marine extract rich in regenerative minerals, protecting hair against daily agressors and providing deep revitalisation.
Pro-Xylane™ A molecule from green chemistry, known for reinforcing fibre structure and increasing hair thickness.
Ochrophyta Algae A bio-sourced marine extract rich in regenerative minerals, protecting hair against daily agressors and providing deep revitalisation.
AQUA / WATER / EAU
•
•
•
•
•
• C13-14 ISOALKANE
•
•
•
•
•
•
• CARVONE
• CITRUS AURANTIUM PEEL OIL
•
• POGOSTEMON CABLIN OIL
•
• LINALYL ACETATE
•
•
• MACROCYSTIS PYRIFERA EXTRACT / KELP EXTRACT
•
• BENZALDEHYDE
•
•
•
• TRIMETHYLBENZENEPROPANOL
• ROSE KETONES
•
• BETA-CARYOPHYLLENE
•
•
•
FRAGRANCE
TOP NOTES
FREESIA, ROSE & MARINE NOTES
HEART NOTES
BERGAMOT, ORRIS & GREEN NOTES
BOTTOM NOTES
MUSK ACCORD, WHITE FLOWERS & PATCHOULI ORPUR
FRAGRANCE
PARIS COUTURE
The Chronologiste fragrance is a revitalising & sensual fragrance, embodying a blend of modernity with retro-classic influence.
PARIS COUTURE
TOP NOTES FREESIA, ROSE & MARINE NOTES
HEART NOTES BERGAMOT, ORRIS & GREEN NOTES
BOTTOM NOTES MUSK ACCORD, WHITE FLOWERS & PATCHOULI ORPUR
The Chronologiste fragrance is a revitalising & sensual fragrance, embodying a blend of modernity with retro-classic influence.
PDP Section UGC Banner
THEY TRIED IT, THEY LOVED IT
Stronger Hair, Stronger Stories. See Chronologiste in action. #TimeIsOnYourSide
THEY TRIED IT, THEY LOVED IT
Stronger Hair, Stronger Stories. See Chronologiste in action. #TimeIsOnYourSide
PDP Section FAQs
FREQUENTLY ASKED QUESTIONS
Do I need to rinse it out in the morning?
No. The formula is designed to be leave-in and absorbs fully overnight with no residue.
Can I use it on both wet and dry hair?
Yes. It can be applied to dry or towel-dried hair as the final step of your evening routine.
Will it make my pillow greasy or sticky?
No. The quick-break texture absorbs instantly, leaving no residue on fabric or hair surface.
What is the scent of this serum?
Chronologiste owns a signature Parisian couture scent, a revitalising and sensual fragrance.
What are the benefits of this serum?
It leaves hair smoother, and more nourished.
PDP Section Routine Carousel
COMPLETE YOUR ROUTINE
CHRONOLOGIST
At Kérastase, we believe in the power of a complete haircare routine. Discover the products of this range and maximise your results!
A revitalising mask - infused with Hyaluronic Acid and Abyssine, this mask is designed for hair weakened by signs of ageing: dryness, dullness, loss of volume and thickness, and frizz.
The refillable Huile de Parfum is a luxurious hair oil infused with Myrrh extract. A few drops leave hair revitalised, moisturised, and delicately perfumed.
Overnight Youth Serum by Kérastase is a night treatment infused with Pro-Xylane™ and Ochrophyta Algae, designed to reverse the visible signs of ageing during nighttime.
One size
90 ml
PDP Reviews
Rated 5 out of
5 by
Style Hair Studio from
Absolutely LOVE![This review was collected as part of a promotion.] I’ve been trialling the Kérastase Chronologiste Overnight Youth Serum for the past month and I’m honestly so impressed.
For context, I’m 29, a hairdresser, and have long, natural hair with bleach highlights (past boob length) so keeping it healthy and smooth is always a priority. I’ve been using this every night and the results are exactly what you’d hope for from a premium overnight treatment.
My hair feels noticeably calmer and de-frizzed by morning, with such a soft, conditioned feel and a really healthy shine. It doesn’t feel heavy or greasy at all, I use just one pump through my mid-lengths and ends (sometimes two, but one is honestly enough).
I’ve also been pairing it with heatless curls on some nights and it works beautifully for smoothing and keeping everything polished.
This has genuinely become a staple on my bedside table, one of those effortless products that makes a visible difference without any fuss.
Date published: 2026-04-12
Rated 5 out of
5 by
Anonymous from
A Luxury night's sleep[This review was collected as part of a promotion.] This light weight night serum extends the life of my blow dry. In the morning, I brush through my hair that has been nourished overnight with Chronologiste Youth Serum and my blow dry feels fresh and airy again with amazing shine. Not to mention the luxurious spa aroma. Highly recommend
Date published: 2026-04-05
Rated 4 out of
5 by
Lynette Headmasters from
Beautiful results[This review was collected as part of a promotion.] After applying to dry hair in the evening, I found the condition of the hair the next day felt smoother and more hydrated. It was less frizzy and had a nice natural shine. I'm not a huge fan of the fragrance, I found it a bit heavy, especially to use it before going to sleep. Having said that, I tried in on my friend and she loves Coco Chanel so she is a huge fan of the product and has already bought it!
Date published: 2026-04-02
Rated 5 out of
5 by
Anonymous from
amazing[This review was collected as part of a promotion.] love it! smells amazing and I wake up with my hair smoother and shiny. Definitely recommend!
Date published: 2026-03-31
Rated 5 out of
5 by
Williams & Hirst from
Incredible results![This review was collected as part of a promotion.] Been testing the new Chronologiste Overnight Youth Serum and it’s seriously impressive. Lightweight, absorbs quickly and doesn’t leave any residue on the hair or pillow. Hair feels softer, smoother and noticeably more hydrated by the morninG!
Date published: 2026-03-26
Rated 4 out of
5 by
Kate francois from
Thicker stronger hair[This review was collected as part of a promotion.] Lovely smell and consistency, easy to use , made my hair feel much smoother and fuller in just a couple of days , my hair tends to be quite frizzy and really helped keep it smooth the next day
Date published: 2026-03-19
Rated 5 out of
5 by
Amy Allsaints Hair from
A Hairdresser’s Trusted Favourite[This review was collected as part of a promotion.] As a hairdresser, I look for products that deliver both performance and finish, and this does exactly that. The hair feels stronger, smoother and more controlled, with a noticeable reduction in frizz and a luminous shine. It’s a luxurious, high-performing product that I confidently recommend to clients.
Date published: 2026-03-19
Rated 5 out of
5 by
Whites Hair & Beauty from
Great product[This review was collected as part of a promotion.] This makes your hair feel amazing, it leaves a shine to the hair and all round is a great product.