Korean niacinamide serums: compare the formula, not just the percentage
Updated September 10, 2026
A 2% niacinamide serum can contain an exfoliant. A 5% one can include rosemary oil. A bottle with “10 TXA 4” on the front has more going on than a bigger dose of vitamin B3. Those details matter when the serum has to share your face with everything you already use.
For the best Korean niacinamide serum shortlist, we'd compare four: AXIS-Y Dark Spot Correcting Glow Serum for a 5% formula with squalane, Beauty of Joseon Glow Serum for its lower niacinamide percentage and cushiony texture, Anua Niacinamide 10 TXA 4 for a combined uneven-tone formula, and COSRX The Niacinamide 15 for a concentrated option with zinc PCA. Each has a reason to consider it and a reason to look more closely.
This comparison uses current ingredient lists, brand directions and US shopping information checked on September 8, 2026. The choices are editorial judgments about formula fit; we haven't conducted a wear test or ranked customer reviews.
AXIS-Y Dark Spot Correcting Glow Serum: 5% with squalane
AXIS-Y puts 5% niacinamide in a 50 mL pump tube alongside glycerin, sodium hyaluronate and squalane. Its official page describes a lightweight texture. This is a useful first comparison if you'd like niacinamide in a formula that also includes moisturizing ingredients, without choosing a 10% or 15% product immediately.
The catch is in the full list: rosemary leaf oil. AXIS-Y says the serum has no artificial fragrance, but that doesn't make it free of aromatic plant oils. If rosemary oil is something you avoid, the 5% headline shouldn't overrule that preference.
The brand directs a small amount over the face or selected areas, then gentle patting. The capped pump may appeal if you dislike handling droppers. Check the current formula and directions on AXIS-Y's product page.
Beauty of Joseon Glow Serum: a cushionier 2% option
The exact product is Glow Serum: Propolis + Niacinamide, with a stated 2% niacinamide and 60% propolis extract. It comes in 30 and 60 mL bottles. Beauty of Joseon describes a thick, honey-like texture, making it worth comparing if watery serums aren't what you enjoy applying.
There's also betaine salicylate in the current ingredient list. The brand's FAQ describes 0.5% BHA; that isn't a claim that the formula contains 0.5% pure salicylic acid. Remember this extra ingredient if your routine already includes exfoliating products. A lower niacinamide percentage doesn't make this a plain hydration serum or guarantee that reactive skin will tolerate it.
BOJ directs two to three drops over the face and neck, tapped in gently. Read the current official formula and our fuller Glow Serum review if this is your leading option. Glow Deep Serum: Rice + Alpha-Arbutin is a different product.
Anua Niacinamide 10 TXA 4: several tone-focused ingredients together
Anua's current US product page states 10% niacinamide, 4% tranexamic acid and 2% arbutin. The 30 mL bottle is therefore a combination purchase: useful to consider if you specifically want those ingredients in one step, rather than buying separate serums for each.
Read the percentages carefully. The list includes both arbutin and alpha-arbutin; the page doesn't identify the full 2% as alpha-arbutin. It also includes ceramide NP, hyaluronic-acid ingredients, plant oils and betaine salicylate. Concentrations for those additional ingredients aren't disclosed on the page we checked.
Anua describes the texture as watery and lightweight, and directs a few drops before moisturizer, morning and night, with daytime SPF 30+. Those are the product directions, not a requirement to begin twice daily. The combination makes it harder to isolate which ingredient agrees with you if you're changing several things at once. Check the current Anua US page against the bottle you're buying.
COSRX The Niacinamide 15: a higher-strength, shorter-list choice
COSRX pairs 15% niacinamide with acetyl glucosamine, zinc PCA and allantoin. The US Ulta listing has 15 ingredients, without listed perfume or an essential oil. That's a useful contrast with AXIS-Y's botanical formula, though a shorter list doesn't promise a gentler experience.
Consider it if you already know you tolerate a concentrated niacinamide serum and specifically want this supporting-ingredient combination. We wouldn't make 15% the default just because your skin is oily, or assume it must work faster than the other three.
Ulta lists the bottle at 0.67 oz and $25. Its directions allow a few drops after cleansing, morning and/or night, with SPF 30 or higher during the day. The exact US formula and directions are on Ulta's COSRX listing. Claims about acne treatment or scar removal aren't the basis for this recommendation.
What the percentage can tell you
It tells you how much niacinamide the brand says is in the formula. It doesn't tell you how much brighter your skin will look, whether you'll like the finish, or how the serum will behave under your sunscreen.
There is research behind topical niacinamide. In a 12-week controlled study, 50 white women with signs of sun-related skin aging applied a 5% niacinamide formula to one side of the face and its base without niacinamide to the other. The study reported improvements including the appearance of pigmented spots. It didn't test these four serums or compare 2%, 5%, 10% and 15% against each other.
That distinction leaves room for a sensible purchase without pretending the largest number wins. Our niacinamide ingredient guide goes deeper into the evidence; here, the practical question is which complete formula you'd actually want to use.
A quick way to narrow the four
Try these three checks before deciding. They work just as well if your shortlist includes another brand.
Start with the products already on your shelf. Look for niacinamide, exfoliating acids and other uneven-tone ingredients in your current serum, toner and moisturizer. You don't need to calculate a combined percentage: layering a 5% serum and a 5% cream doesn't turn them into a tested 10% formula. You're checking for repeated jobs and unnecessary purchases.
Then cross out known mismatches. If you avoid rosemary oil, remove AXIS-Y. If you're specifically avoiding a serum containing BHA, reconsider both BOJ and Anua because their lists include betaine salicylate. If you don't want propolis, BOJ isn't your candidate. This gets you further than choosing “sensitive skin” on a shopping filter and hoping every remaining bottle feels alike.
Finally, choose what you'd like to change. For example, someone replacing a watery serum with something cushionier has a reason to compare BOJ. Someone who wants niacinamide plus TXA together has a reason to examine Anua. Someone happy with their current niacinamide moisturizer may have no reason to add any of them. If hydration is your main aim, the broader Korean serum guide includes other formulas to consider.
Compare the amount, then the delivered price
These were the displayed prices when checked. They exclude shipping and tax, and sale prices can change.
AXIS-Y, 50 mL: $17.99 sale, $24 regular; about $3.60 per 10 mL at the sale price.
BOJ Glow Serum, 30 mL: $15.30 sale, $17 regular; $5.10 per 10 mL at the sale price.
COSRX The Niacinamide 15, 0.67 oz: $25 at Ulta for a single purchase, before any subscription offer.
AXIS-Y's official store says orders ship from South Korea and that destination-related charges may apply. A lower bottle price isn't necessarily the lowest delivered total for a US shopper. Compare the same product, size and seller terms before checkout. None of these price differences measures how well a serum will work for you.
Introducing the serum without changing everything else
Keep your familiar cleanser, moisturizer and sunscreen while you introduce the serum. Changing three treatment products together makes the result difficult to judge, whether your skin looks better or feels irritated.
Follow the specific bottle's application directions and introduce it gradually. You don't have to increase use simply because the label permits morning and night. If a reaction develops, wash the product off and stop using it. Get professional advice for a severe or persistent reaction instead of treating burning as proof that a serum is working.
For uneven tone, skincare also needs to address what's causing the marks. The AAD's dark-spot guidance emphasizes sun protection and avoiding irritation; a stronger serum can't take over that job. Our Korean skincare guide for dark spots explains the wider choices.
Do you need to move up to a stronger bottle later?
There's no automatic progression from 2% to 5% to 10% to 15%. Finishing a bottle comfortably doesn't mean you've outgrown it.
Before replacing it, separate what you know from what you hoped for. Did the texture suit you? Was it easy to use consistently? Did the specific concern you were watching change, without a whole new routine arriving at the same time? A repeat photo in similar lighting can help you compare appearances, although it won't establish what caused a change.
If you're happy with the product, repurchasing it is a perfectly reasonable choice. If you're disappointed, write down whether the problem was the finish, the price or the result. That gives the next purchase a much better brief than “more niacinamide.”
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A researched look at Anua Niacinamide 10 TXA 4 Serum: its exact formula, review evidence, directions and whether it duplicates products you already use.
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