COSRX The 6 Peptide Skin Booster Serum (150 mL)

This product is accurately described as a toner serum. It has the lightweight, fast-absorbing texture of a toner, but functions more like a treatment serum. Rather than focusing only on hydration, its real strength is how well it prepares the skin and enhances the performance of products applied afterward.With consistent use, I’ve noticed clearer skin, a brighter and more even tone, and gradual improvement in dark spots. The effect is especially noticeable when pairing it with active treatments such as vitamin C serums.How I use it (evening routine):In the evening, I apply a thin layer and gently pat until fully absorbed, then repeat this step 2–4 times, depending on how dry my skin feels that day. Building hydration gradually this way allows the skin to absorb moisture without heaviness and noticeably improves plumpness and overall moisture retention.Once the toner serum is fully absorbed, I apply my treatment serums (such as vitamin C), followed by a moisturizer with enough oil and hydration to seal everything in. Used this way, it clearly improves how well active serums absorb and perform, leaving the skin looking fuller, healthier, and well-hydrated.Morning use:I also use this in the morning, but usually apply just one light layer. It noticeably improves makeup application—foundation goes on more evenly, adheres better, and stays comfortable throughout the day without emphasizing dryness.I hope this review is helpful for anyone deciding whether this fits into their routine.

Love this product. I use it all over my face, even over my eyelids. I’ve stopped using eye creams. I’ve gotten compliments on the brightness of my skin since starting this. Very liquidy, so be careful when applying. No skin irritation, very healing and doesn’t burn or hurt on compromised barrier. Bottle itself is very sturdy, but a stiff wind will knock the cap off lol very effective product, and awesome value for the product you get imo. I will continue to repurchase.

One of my “hobbies” is trying skin care stuff and I have been on repeat recommending this to everyone! It is one of those rare products I have actually SEEN a difference in my skin. Not just “oh, maybe my skin is a little more hydrated” but actually getting complimented from people on how smooth and good it looks. Plus the price point is unbeatable. I see some improvement with fine lines, very brightening, mildly hydrating (not going to replace an actual lotion though), but where it really shines is calming any angry skin. If I see some redness cropping up or a pimple, this just calms it right down. Most of the time the pimple never even fully forms! But let me be transparent, I don’t suffer from severe acne- I just get the occasional, usually hormonal, pimple so I can’t speak to those dealing w cystic acne etc. I have recommended it a lot to my coworkers bc I’m in healthcare and a lot of us deal with “mask-ne”.It’s a good sized bottle, I’m barely halfway thru it after weeks and I use it everyday. No scent. Watery texture so it absorbs quickly, doesn’t interfere with my makeup. Honestly just blown away how well it works for a relatively inexpensive (especially in the skin care world) product. 10/10!

Love Cosrx - it's one of my go-to skincare brands and I am rarely disappointed.This 6x Peptide Collagen Booster Toner is one of my favorites and I have repeat ordered. But it does last a long time as a little goes a long way so I don't have to order it that often.It glides on beautifully and gives my skin such a nice glow.It's not greasy at all. It absorbs quickly.I like to order it on sale or on Prime day as I did this time but all of Cosrx's prices are reasonable, which makes this brand even better as the value is so great.This toner/serum is very hydrating. My skin loves it. I can get Rosacea redness and this doesn't irritate my skin at all--no redness, no itchy feeling, no irritated skin.Fragrance free.Just love it!

Smooth, gentle on skin. No irritation, dries quickly.

Wow.Years ago (I'm 52), in the mid-aughts when I started realizing I needed to care for my skin, quality products (outside Cera Ve) either required a prescription or were awfully expensive. You really had to pick and choose what you purchased, and it always came at a cost. Fast forward to now, and the product lines like COSRX , The Ordinary, the Inkey and more really have brought incredible skin care to an affordable price point.I was looking for a copper peptide serum that was a little less expensive than the one I was using ($40 for a .5 oz bottle). I saw this on special and decided to try it out, as I have liked some of their other products.I'm quite impressed after using for a little less than a week. One thing I think this does is really help distribute my other serums more evenly; in addition to copper peptides and nianamiacde in my regular rotation I use a growth factors serum, azelaic acid, and vitamin C, but I always feel like I have issues getting coverage. By starting with this, then layering the others, I find I get much better coverage. In general, just a few days in my skin is looking much more hydrated and even my fine lines and wrinkles are less prominent. (Its almost winter in Maine right now and hydration is a serious challenge.). The woman who put this on her lips - thank you! Genius. It really makes a difference.In addition to this, I find this product alone leaves my skin really smooth and hydrated under makeup. Its super lightweight and really helps achieve a good finish, and really lasts all day to boot. While Im a little old to achieve a "glass" finish I imagine a younger person could really nail that look with this.

Excellent product! This is a great product to use after cleansing your skin. My skin type is combination and very sensitive. I often breakout or get a rash from trying new products, but I did not with this. It is very gentle and works great for sensitive skin. My skin tends to get very dry during winter as I live in the north. This helped to keep my face more balanced and not as dry without it feeling sticky as some products feel. I use 1-2 pumps onto my fingertips and spread it evenly all over my face. I do another 1-2 pumps for my neck as well. This leaves my skin with a natural glow (not greasy looking). Make sure it fullly dries before applying your next step in your skin routine or applying makeup.

This booster serum is a powerhouse. It feels like a professional skincare treatment in a bottle. The formula is incredibly lightweight, almost watery, but it delivers intense hydration and firmness. My skin feels bouncy, smooth, and refreshed immediately after application.After consistent use, I noticed improved texture and a subtle tightening effect — especially around my cheeks and jawline. It layers perfectly with other products and never pills. The combination of peptides and niacinamide makes my skin look brighter and more even.This is one of those products that quietly upgrades your entire routine. It’s gentle, effective, and suitable for daily use. If you want that glass-skin glow, this is a must-have.