Kiehl's Clearly Corrective Dark Spot Solution is one of the most popular vitamin C serums, with over 1,400+ reviews across Kiehl's, Ulta Beauty, and Sephora.
If you're reading my review, then you probably fall into one of two groups:
In either case, I'll help you understand if this product is for you (or a quick pass).
Let's get started! ⭐
First of all, a good Vitamin C Serum serve 3 main functions:
Second of all, there are 2 general types of Vitamin C:
Kiehl's uses a vitamin C derivative called 3-O-Ethyl Ascorbic Acid (EAC):
Overall, EAC is a stable but less studied vitamin C derivative. Further studies are required to determine its ability to promote collagen growth and provide antioxidant protection.
Kiehl's also included two natural skin brightening ingredients:
Finally, if you have more sensitive skin, please be aware that Clearly Corrective contains alcohol (drying) and lavender oil (fragrance). As always, do a patch test first.
Overall, I give the ingredients a score of 3.0. (not bad, but could be better)
When it comes to product design, I’m mainly focused on overall functionality and usability, although I do occasionally give bonus points for exceptional aesthetics.
For vitamin C serums, it’s important to protect the contents from light, air, and heat since vitamin C (especially LAA) will naturally oxidize over time and lose its potency.
In this case, I docked marks from Kiehl's for using a transparent glass bottle which does not offer any protection from UV light exposure.
However, since Kiehl's uses a vitamin C derivative (EAC), it's not a huge deal-breaker, as EAC is more stable compared to LAA (which is known to oxidize very quickly).
In addition, the dropper design has a fatal flaw as well. Every time you open the bottle, you're letting fresh air (oxygen) in, which accelerates the natural oxidation process.
Over time, this will reduce the potency of antioxidants like White Birch and Peony Root.
That's why you should keep this product in a dark, cold place (the fridge works perfectly) and make sure to use it regularly so it's not sitting around and losing its effectiveness.
The gold standard in product design is an opaque container with a pump dispenser (Drunk Elephant C-Firma Day Serum is a good example).
Overall, I give the product design a score of 3.0. (does not effectively limit oxidation)
Clearly Corrective Dark Spot Solution has the consistency of a light and watery serum. I found it was easy to apply and also provided a refreshing sensation on my skin.
You might feel a bit of warmness upon application as well (it goes away quickly).
I recommend using about 3-5 drops for your entire face and 5-10 drops if you want to cover your neck, chest, and hands. Allow 2 minutes to dry before applying makeup or SPF.
Clearly Corrective also has a mild floral scent that I believe is primarily lavender oil (perhaps in combination with orange peel extract which is also on the ingredient list).
Personally, I don't mind the fragrance but I know it may cause adverse skin reactions for some people. Again, perform a patch test or try a sample size first.
Overall, I give the texture & smell a score of 4.5. (light watery texture, mild floral scent)
Of course, the most important question is, does Kiehl's dark spot corrector actually work?
Personally, I've only tested a few sample packs that I received from a Kiehl's store:
In the future, I'd like to run a longer study (3+ months) with before/after photos as well.
In terms of community feedback, there's over 1,400+ reviews between Kiehl's, Ulta Beauty, and Sephora, with a consensus rating of ~3.6 stars.
After reading the reviews, it's clear this product has been hit-and-miss for most people, either helping to reduce dark spots and brighten skin tone, or just... meh ????♀️.
I think it's possible these ratings are a reflection of the low effectiveness of EAC or perhaps the inadequate concentration of EAC (Kiehl's doesn't disclose the percentage).
Overall, I give the results a score of 3.0. (my skin felt clearer & smoother after a few days, but overall reviews are fairly hit-and-miss in terms of dark spot reduction)
While Clearly Corrective is not cheap, it’s not completely unaffordable either.
(ahem, looking at you, SkinCeuticals C E Ferulic!)
At $56 per oz, Kiehl's is actually reasonably priced for a mid-range beauty brand.
For the best value, I recommend the Clearly Corrective Dark Spot Solution Duo which is a 2-pack of 1.7 oz (50 mL) bottles for only $138 (this works out to under $41 per oz).
The Duo is much better than the 3.4 oz mega size as you can keep the second bottle safely in storage so it doesn't lose its effectiveness from air, light, and heat exposure.
Or you can give the second bottle to your friend or family member (it's the perfect gift!).
For comparison's sake, let's look at similar products that use 3-O-Ethyl Ascorbic Acid:
For more information, I’ve put together a spreadsheet of the most popular products, including price, price per oz, and key ingredients, for quick and easy comparison.
Overall, I give the price a score of 3.5. (it’s not cheap, but it’s not unaffordable either)
Finally, I’ve handpicked two customer reviews that I feel are fair and representative:
"I was a little hesitate on the price, but I was pleasantly surprised when I bought the 3.4 oz bottle and it lasted over 5 months (applying both day and night). This product needs time and commitment. It's not going to give you perfect skin overnight, the results are gradual. Whenever I would pop anything on my face I would have a dark discoloration that would lasts weeks and sometimes even months! Since using Clearly Corrective Dark Spot Solution I have noticed that these dark spots fade much faster and that is why I have kept it in my routine. The process takes time and the price is a bit expensive, but it is well worth it."
"It has a very light fragrance and it is effective if you want it to brighten up your skin. My impression upon buying it was that it would lighten my dark spots (sunspots). However, there is absolutely no difference with my sun spots. I would much rather use The Ordinary’s Niacinamide 10% and Zinc 1% solution than this for correcting dark spots. This Kiehl’s product is rather effective for brightening my complexion and making it less dull. I have noticed while applying foundation that I had a more even skin tone. I applied this product on my upper lip hoping that it would lighten my moustache region but I did not see a difference."