Ask any skincare guru what the best BHA exfoliant out there is and they’ll say Paula’s Choice Skin Perfecting 2% BHA Liquid Exfoliant.

For years, it literally had no competition. Everything else either had too little BHA or a pH that deactivated it. Now, Cosrx BHA Blackhead Power Liquid is threatening to knock its off its throne.

Those who tried it swear the Korean newcomer does a better job: it works faster, it’s gentler and doesn’t leave your skin an oily mess.

Should you switch? Let’s find out:

What Ingredients Do These BHA Exfoliants Have In Common?


Technically, Paula’s Choice Skin Perfecting 2% BHA Liquid Exfoliant and Cosrx BHA Blackhead Power Liquid are both BHA exfoliants. But, they DON’T use the same form of BHA.

Paula’s Choice uses Salicylic Acid, an oil-soluble exfoliant that dissolves the “glue” that holds skin cells together, so they can slough off your skin instead than getting stuck in your pores and clogging them up.

While it’s at it, it also gets inside the pores to get rid of all the crap that’s accumulating in there. That’s what makes it such a good fighter against blackheads, whiteheads and pimples.

Plus (yep, salicylic acid has more than one superpower), it has anti-inflammatory properties that reduce irritations and redness.

Salicylic acid is commonly used everywhere… apart from Korea. The country has very strict laws about salicylic acid use in skincare (funny when you think Koreans put literally anything – from snail slime to jellyfish – into their products!). Brands get around them by using a different version of salicylic acid: betaine salicylate.

(FUN FACT: Paula’s Choice uses betaine salicylate in the BHA exfoliants it sells in Korea. 🙂 )

But is betaine salicylate as effective as salicylic acid?

We don’t know. The manufacturer swears it is – if you use double the amount! So, to get the results 2% salicylic acid gives you, you need to use 4% betaine salicylate.

FYI, some websites that sells Cosrx BHA Blackhead Power Liquid proudly boast that it has 4% BHA. This is to trick you into thinking that’s more powerful than Paula’s Choice and other exfoliants that use 2%. But if this study is true, that’s BS. It has more because you need to use more to get the same results. Don’t fall for it!

Related: Why Salicylic Acid Is The Key To Spot-Free Skin

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What Else Is In These BHA Exfoliants?

Not only Cosrx BHA Blackhead Power Liquid and Paula’s Choice Skin Perfecting 2% BHA Liquid have a different active ingredient. The rest of the formulas are different too!

Cosrx is more hydrating. It has hyaluronic acid, a moisture magnet that attracts and binds to the skin up to 1000 times its weight in water. Plus, a big dollop of niacinamide, a multitasker that hydrates skin, soothes irritations, reduces fine lines, fades away dark spots and treats acne. You name it, it does it!

Paula’s Choice is a little oilier. It has a big drop of methylpropanediol, another moisture magnet. But unlike hyaluronic acid, it makes your skin look a bit greasy (not the best look if your skin’s already oily). But it has green tea to soothe irritations and fight wrinkles.

Related: Why You Need To Add Hyaluronic Acid To Your Skincare Routine, No Matter Your Skin Type

What’s The Texture Like?

Paula’s Choice Skin Perfecting 2% BHA Liquid has an oily texture that leaves a shiny sheen on skin.

Cosrx BHA Blackhead Power Liquid has a lighter texture oily skin will appreciate more.

What’s The Packaging Like?

Paula’s Choice Skin Perfecting 2% BHA Liquid comes in a dark bottle with a pump applicator. Sleek and practical.

Cosrx BHA Blackhead Power Liquid comes in a see-through bottle with a pump applicator. It looks less elegant, but it’s just as practical.

How To Use Them

Every other night, after cleansing.

If your skin breakouts a lot AND is resistant, you can get away with using it every day.

Which Of The Two Should You Go For?

I’m a sciencey beauty blogger. I have to recommend you to go with Paula’s Choice simply because salicylic acid is tried and tested while studies on betaine salicylate are still lacking. *sighs*

And if salicylic acid is already working wonders for you, why rock the boat and switch things up? If the oily finish really bothers you, Paula’s Choice has plenty of other products with salicylic acid. Check this quick guide here to find out the right one for you.

But if your skin’s so sensitive it can’t tolerate salicylic acid, then betaine salicylate is well worth a try. 

Related: The Complete Guide To Paula’s Choice BHA Exfoliants: Which One Is Right For You?

Price & Availability

Cosrx BHA Blackhead Power Liquid: £22.00 at Beauty Bay, Dermstore, Feel Unique, Look Fantastic, Ulta and Yes Style

Paula’s Choice Skin Perfecting 2% BHA Liquid: $29.00 at Cult Beauty, Dermstore, Feel Unique, Paula’s Choice, and SpaceNK

Is Cosrx BHA Blackhead Power Liquid A Dupe For Paula’s Choice Skin Perfecting 2% BHA Liquid?

Nope. They have completely different ingredients! But Cosrx BHA Blackhead Power Liquid is a gentler version of Paula’s Choice Skin Perfecting 2% BHA Liquid. If you have sensitive skin, give it a try.

Cosrx BHA Blackhead Power Liquid Ingredients

Salix Alba (Willow) Bark Water, Butylene Glycol, Betaine Salicylate, Niacinamide, 1,2-Hexanediol, Arginine, Panthenol, Sodium Hyaluronate, Xanthan Gum, Ethyl Hexanediol

Paula’s Choice Skin Perfecting 2% BHA Liquid Ingredients:

Water (Aqua), Methylpropanediol (hydration), Butylene Glycol (hydration), Salicylic Acid (beta hydroxy acid/exfoliant), Polysorbate 20 (stabilizer), Camellia Oleifera Leaf Extract (green tea/skin calming/antioxidant), Sodium Hydroxide (pH balancer), Tetrasodium EDTA (stabilizer)