Your Guide to Face Serums: Vitamin C, Retinol, and CELESTii
If your skincare routine stops at cleanser and moisturizer, you're missing the step that does the most targeted work: the serum.
Serums are lightweight, fast-absorbing formulas with a high concentration of active ingredients. Because they're made of smaller molecules than most creams, they penetrate deeper into the skin and deliver their ingredients where they can actually make a difference, rather than sitting on the surface. Think of your moisturizer as the seal that locks hydration in, and your serum as the ingredient that does the heavy lifting underneath it.
When should you apply a serum? Most serums work best on clean, slightly damp skin, right after cleansing (and toning, if you use one) and before moisturizer. Damp skin helps water-based serums absorb more evenly. Some serums are formulated for morning use, others for night; we'll cover which is which below.
Where does a serum fit in your routine? As a general rule, apply products from thinnest to thickest consistency:
- Cleanser
- Toner (optional)
- Serum
- Moisturizer
- Sunscreen (AM only, always)
This order lets each product absorb fully before the next one goes on.
What are serums best for? Different serums target different concerns: brightening, fine lines and wrinkles, firmness, texture, dark spots, and hydration. Below, we break down our three serums, what's in them, and what each one is best suited for, so you can build the routine that fits your skin.
1. Vitamin C Facial Serum ($48)
Best for: hyperpigmentation, dullness, dehydration, early signs of aging
When to apply: Morning, after cleansing and before moisturizer and sunscreen.
Vitamin C is one of the most well-studied ingredients in skincare, and for good reason. Our formula contains 20% ascorbic acid (the purest, most active form of Vitamin C), which stimulates your skin's natural collagen production and helps fight free radical damage from everyday environmental stressors like UV exposure and pollution. It's a powerful treatment for hyperpigmentation, dullness, and dehydration, leaving skin looking brighter, more even, and more resilient.
Because of its protective, antioxidant role, Vitamin C is best worn during the day. Layered under your sunscreen, it helps your skin put up a stronger defense against the stressors it will face throughout the day.
Other key ingredients included in our Vitamin C Face Serum:
- Hyaluronic Acid (botanically derived): Draws moisture into the skin to keep it hydrated and plump, balancing out Vitamin C's brightening work with lasting hydration.
- Witch Hazel: A natural astringent that helps tighten the appearance of pores, giving skin a smoother, more refined look.
The formula also includes organic jojoba oil to moisturize the face, is made with 98% naturally derived ingredients, and is vegan, cruelty-free, paraben-free, phthalate-free, sulfate-free, silicone-free, and gluten-free.
Shop the Vitamin C Facial Serum →
2. Radiance Retinol Face Serum ($62)
Best for: fine lines, wrinkles, dull or uneven texture
When to apply: Evening only, after cleansing and before moisturizer.
Retinol is a derivative of Vitamin A and one of the most effective ingredients available for addressing visible signs of aging. It works by encouraging skin cell turnover, which helps smooth the look of fine lines and wrinkles, refine texture, and support a more even, radiant complexion over time. This serum is expertly formulated to smooth, hydrate, and brighten the appearance of skin, minimizing the look of fine lines and wrinkles while soothing and nourishing along the way, ideal for anyone chasing a more youthful, refreshed glow.
Retinol can make skin more sensitive to sunlight, so it's best to apply at nighttime. While you sleep, it gets to work on renewal without the risk of sun exposure counteracting its benefits. Always follow with sunscreen the next morning if retinol is part of your routine.
Other key ingredients of our Retinol Radiance Face Serum:
- Witch Hazel: A natural astringent that helps tone the skin and refine the look of pores, complementing retinol's smoothing effect.
- Aloe Vera: Soothes and nourishes skin, helping offset any dryness or sensitivity that can come with retinol use, especially early on.
Shop the Radiance Retinol Face Serum →
3. CELESTii Face Serum 3D ($38)
Best for: wrinkles, elasticity, deep hydration, overall skin renewal
When to apply: Anytime, morning or night.
CELESTii is in a different category altogether. Where most serums rely on familiar hero ingredients like Vitamin C or retinol, CELESTii is powered by biomimetic technology, a formula inspired by zero-gravity research, where skin-supporting bio-molecules thrive. That's the "unusual" part of this serum: rather than a single active ingredient, it's built around a nutrient-dense delivery system designed to work with the skin the way these bio-molecules behave in a zero-gravity environment.
The result is a formula that locks in 10x more hydration than a typical serum, visibly smooths the look of wrinkles, boosts elasticity, and deeply hydrates for a plumper, more radiant complexion. It's clinically shown to deliver real results, supporting the skin's natural renewal process for a firmer, smoother, glow-from-within look.
What makes our CELESTii Face Serum unique:
- Biomimetic, zero-gravity-inspired technology: The formula's bio-molecules are designed to mimic conditions where skin-supporting molecules are naturally more active, which is the science behind the "3D" positioning, a departure from a standard single-layer, single-ingredient serum.
- 10x Hydration Lock: Helps skin retain significantly more moisture than a typical serum, supporting the plumper, firmer look the formula is known for.
Building Your Routine
You don't have to choose just one. A simple, effective routine looks like:
- Morning: Cleanser → Vitamin C Serum (or CELESTii) → Moisturizer → Sunscreen
- Evening: Cleanser → Retinol Serum (or CELESTii) → Moisturizer
If you want to use more than one serum in the same routine, space them out: Vitamin C in the morning, Retinol at night, rather than layering them together, since Vitamin C and Retinol can be less effective (and more irritating for sensitive skin) when applied at the same time. CELESTii can be used daily alongside either, depending on your skin's needs.
Whichever you choose, consistency matters more than any single ingredient. Give a new serum 4–6 weeks before judging results and always patch test when introducing something new.
