SUNNYSIDE 15% Vitamin C Brightening Day Serum

The situation: Uneven.

active-tolerant skin · hyperpigmentation · dull skin | seasonal shift · dry & dehydrated · fine lines & wrinkles

15% Vitamin C that stays stable long enough to actually work.

$79.00

Free shipping on orders $75+

Most Vitamin C serums oxidize before they reach their potential. Sunnyside uses two oil-soluble, highly stable derivatives — Tetrahexyldecyl Ascorbate and 3-O-Ethyl-L-Ascorbic Acid — at a combined 15% concentration, formulated to stay potent from first pump to last. Visibly improves the appearance of dark spots and uneven skin tone.

What it feels like

Balanced serum consistency — not runny, not heavy. Presses smoothly into skin. Leaves skin feeling hydrated, soft, and visibly luminous within minutes.

Top benefits

— 15% stable Vitamin C (Tetrahexyldecyl Ascorbate + 3-O-Ethyl-L-Ascorbic Acid) visibly improve the appearance of dark spots, loss of firmness, and free radical damage
— 3% Tranexamic Acid visibly improve the appearance of dark spots and uneven pigmentation
— 2% Niacinamide minimize the appearance of pores, oiliness, and visible irritability
— 2% MossCellTec improve skin resilience and moisture retention

Aloe Barbadensis Leaf Juice, 3-O-Ethyl Ascorbic Acid, Caprylic/Capric Triglyceride, Simmondsia Chinensis (Jojoba) Seed Oil, Tetrahexyldecyl Ascorbate, Tranexamic Acid, Caprylyl Caprylate/Caprate, Glycerin, Niacinamide, Isomalt, Vitis Vinifera (Grape) Seed Oil, Glyceryl Stearate, Cetearyl Glucoside, Glutathione, Tremella Fuciformis Sporocarp Extract, Inonotus Obliquus (Mushroom) Extract, Sodium PCA, Tocopherol, Water (Aqua) (Eau), Citric Acid, Cetyl Alcohol, Phytol, Benzyl Alcohol, Hydroxyethylcellulose, Dehydroacetic Acid, Benzoic Acid, Sorbic Acid, Maltodextrin, Disodium Phosphate, Polysorbate 60, Sodium Phosphate

AM: On clean, dry skin, gently press 1–2 pumps onto face, neck, and chest, avoiding the eye area. Allow to absorb before the next step.

AM Routine: Utopia → Galilee → Sunnyside → Owel → Grand → SPF

Note on pump residue: A small amount may dry in the nozzle between uses. Dispense gently for the first pump of each session.

Pore Confession: Sunnyside is your AM active. Moonbeam is your PM active. They work the same skin renewal pathway from opposite directions — Vitamin C protecting and brightening by day, retinaldehyde renewing overnight. Use both consistently for compounded results.

Skin appears more luminous and hydrated immediately after application.

A good skincare routine requires dedication (that's on you) – With consistent use, complexion appears visibly brighter and more even.

Build Your Skin Strategy

Sunnyside is your AM active. Moonbeam is your PM active. Together they cover the full 24-hour renewal cycle. In the AM, Sunnyside sits after Galilee to amplify antioxidant defense before Vitamin C is applied.

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Fragrance Free
Cruelty Free
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Non-Foaming
Sunnyside 15% Vitamin C Brightening Day Serum Retail IDF

Sunnyside 15% Vitamin C Brightening Day Serum

$79.00

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Understanding Vitamin C Derivatives

Despite traditional Vitamin C's (aka Ascorbic Acid) notorious instability in cosmetic formulations, derivatives like Tetrahexyldecyl Ascorbate and 3-O-Ethyl-L-Ascorbic Acid rise above to deliver maximum results without the shortened shelf life or oxidative risks. These oil-soluble derivatives don't just boast enhanced stability to preserve their efficacy, their superior skin penetration capabilities optimize the absorption and delivery of vitamin C's high-performance benefits like brightening, antioxidant defense, and the stimulation of collagen synthesis while remaining gentle enough for sensitive skin types.

Our key ingredients

  • 15% Vitamin C Combo

    (Tetrahexyldecyl Ascorbate + 3-O-Ethyl-L-Ascorbic Acid): Two highly stable, oil-soluble Vitamin C forms chosen for penetration depth and oxidative stability. Target dark spots, sagging, and free radical-related skin damage.

  • 3% Tranexamic Acid

    Visibly improve the appearance of dark spots and UV-induced pigmentation.

  • 2% Niacinamide

    Vitamin B3 that helps diminish the look of enlarged pores, excess oiliness, and visible irritability.

  • 2% MossCellTec

    Active extracted from biotechnologically-produced moss. Improves skin resilience, moisture retention, and antioxidant defense.

"Sunnyside Delivers! Since using Sunnyside Serum, my skin truly feels so much younger. This serum delivers on everything as described; the bounce, the glow, the smooth feel and look! It's a great product."

— Grace F.  Verified Purchase

The HoliFrog Difference

Holistic Functional

Holistic Functional

Every ingredient matters.

Percentages Matter

Percentages Matter

Quality needs quantities.

Skin Strategy Over Skin Type®

Skin Strategy Over Skin Type®

Skin type is a starting point, not a sentence.

Holistic Functional

Holistic Functional

Every ingredient matters.

Percentages Matter

Percentages Matter

Quality needs quantities.

Skin Strategy Over Skin Type®

Skin Strategy Over Skin Type®

Skin type is a starting point, not a sentence.

Build your skin strategy

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Overall rating: 4.4615383 / 5 from 26 reviews.

AI Generated Review Summary

Sunnyside 15% Vitamin C Brightening Day Serum is praised for its ability to make skin feel younger and smoother, while some customers find it irritating and sticky.

Summary topics

  • Product Feel: 39%
  • Skin Improvement: 34%

Review topics: [].

Review highlights

  • "it makes my skin feel so soft and ready for my moisterizer." — Donna C.
  • "My skin looks and feels smoother, even toned, and I must say I'm shocked when I look in the mirror." — Patty
  • "It hydrates and makes my skin feels so smooth." — Tracey

Reviews

Vitamin c

"I love your skin care line for acne, am pore control, because really work to clean up my skin."

— Jennifer K. (5/5)

Working Nicely!

"Im 50 with aging skin, fine lines, wrinkles, dark spots. Im definitely the test subject for high end skincare. This Vit C is actually doing its job. I wear a full face of makeup and it plays nicely, no pilling. My dark spots are completely gone in some areas and fading in all areas. Skin looks brighter and firmer. I’m impressed and very happy to have found this Vit C because it’s affordable and working, finally!"

— Courtness (5/5)

Vitamin C that I recommend

"My favorite vitamin C for dry skin"

— Halina A. (5/5)

Great Product

"I love this product. it makes my skin feel so soft and ready for my moisterizer."

— Donna C. (5/5)

Sunnyside C Glow Serum

"I really like the Sunnyside C Glow Serum and that it has more vitamin C in it than most vitamin C serums on the market."

— Kimberly M. (5/5)

Sunnyside yay!

"Love it! So light and fresh."

— Josephine G. (5/5)

Best product

"Best product"

— Moldir Z. (5/5)

Better than $$$ vitamin c serums!

"My dermatologist said I should be using a vitamin c product daily and recommended Skinceuticals. I have to say I loved it but didn’t like the $182 price tag. I tried this holifrog one and I think it works just as well and I love the feel of it and I especially love the price tag. I love it and am ordering it again!! Also, the other brand isn’t clean like holifrog is."

— Suzanne (5/5)

Tacky

"Perhaps it's a bad batch but the Sunnyside serum does not feel like it absorbs into the skin. No matter how little I use, the serum just sits on my skin. When I apply the Grand cream after the serum, some areas on my face will pill up the serum. I like the ingredients but not a fan of the way it behaves. I've been hate using it for about a month now and have noticed that my skin isn't as smooth as it used to be. I'm also not a fan of the bottle because I'll need to take the lid off to reach the last of the serum. This should really be in an airless pump or squeeze tube. I don't think I would repurchase this product as is or recommend."

— Matt (2/5)

Not for sensitive skin

"Unfortunately the serum caused me a terrible irritation to the skin"

— Egle (1/5)

Q&A