a dupe for the ordinary lactic acid

Is The Inkey List Lactic Acid Serum a dupe for The Ordinary Lactic Acid 10% + HA?

The two exfoliants are so similar, it makes you wonder if The Inkey List took a little too much inspiration from The Ordinary…

But there are a couple of details that make them stand out on their own. Here’s everything you need to know about these exfoliants so you can pick the right one for YOUR skin:

What Key Ingredients Do The Inkey List Lactic Acid Serum And The Ordinary Lactic Acid 10% + HA Have In Common?


Lactic acid is the star of the show both in The Inkey List Lactic Acid Serum and The Ordinary Lactic Acid 10% + HA. Duh!

Lactic acid is a member of the Alpha Hydroxy Acids (AHAs) family, a group of exfoliant that dissolves the glue that holds skin cells together.

When you get rid of this superficial, damaged layer, your skin takes on a dewy glow. Dark spots start to fade away. The whole complexion is softer and smoother.

Plus, lactic acid is hydrating. It works thanks to a humectant mechanism, a fancy way of saying it draws moisture from the environment into the skin.

The catch? Lactic acid is a bigger molecule than it sibling Glycolic Acid (another AHAs). You know what it means?

Bad news: It’s not as effective. It takes longer to work and fade away discolourations and other skin imperfections.

Good news: It’s much gentler for sensitive skin. Lactic acid is usually well-tolerated even by people who can’t stand Glycolic.

If you have sensitive skin, the trade-off is worth it.

P.S. Lactic acid is pH sensitive. If the pH is too low or too high, it won’t work. Luckily both exfoliants are formulated within the right pH to make lactic acid work its magic (TO has a pH of 3.8; TIL a pH of 3.6).

Related: Glycolic Acid VS Lactic Acid: Which One Is Right For You?

​If you’re worrying about doing The Ordinary wrong, get your butt on this The Ordinary speed training (affiliate link). It’s by my scientist friend Cheryl Woodman and in it she’s teaching you how to use The Ordinary to get makeupless skin you love.

The Ordinary Skincare Routine - Where to start with The Ordinary skincare


Both The Inkey List Lactic Acid Serum and The Ordinary Lactic Acid 10% + HA contain Hyaluronic Acid, a powerful moisture booster.

Hyaluronic Acid acts like a magnet: it attracts water from the environment (both the air around you and the deeper layers of your skin) and dumps it into the superficial layers of your skin.

All that extra moisture plumps up skin, so its fine lines and wrinkles look smaller. It makes skin softer to the touch. And it gives the complexion a dewy glow.

P.S. Hyaluronic Acid isn’t as drying as you think. Your skin is made up of mostly water, so HA only redistributes it to the layers that need it most.

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

What Else Is In These Exfoliants?

Both exfoliants have fairly basic, if slightly different, formulas.

The Ordinary Lactic Acid 10% + HA has a drop of Tasmanian pepperberry, a little berry rich in flavonoids, a family of antioxidants with anti-inflammatory properties. It reduces redness and irritation and helps sensitive skin better tolerate lactic acid.

The Inkey List Lactic Acid Serum has a drop of moisturising castor oil and Agastache mexicana extract, a plant which has antioxidant properties. 

Related: The Complete Guide To Castor Oil In Skincare: What It Is, What It Does, And How To Use It

What’s The Texture Like?

The Inkey List Lactic Acid Serum has the edge here. It has a watery-like texture that absorbs immediately into the skin.

The Ordinary Lactic Acid 10% + HA isn’t as elegant. It feels a little sticky on the skin, but the annoying sensation disappears once you start layering on your skincare.

What’s The Packaging Like?

The Ordinary Lactic Acid 10% + HA comes in a frosted-glass bottle with a dropper applicator. Practical and convenient to use.

The Inkey List Lactic Acid Serum has opted for a white and black bottle with a big opening that always dispenses more product than you need. Be careful!

How To Use Them

If you have sensitive skin, don’t use lactic acid more than once or twice a week. More exfoliation won’t give you brighter, smoother skin. It’ll just give you a bad case of irritation.

For best results, use them at night straight after cleansing. Don’t use Vitamin A afterwards.

Related: How Often Should You Exfoliate With AHAs/BHA?

Which Of The Two Should You Go For?

This time, it all comes down to personal-preference. The formulas are so similar, it’s the texture or packaging that’ll seal the deal.

P.S. I prefer The Ordinary just because I find The Inkey List has an annoying packaging. But the latter does have a better texture.


The Inkey List Lactic Acid Serum (£7.99): Available at Asos, Cult Beauty, and Feel Unique

The Ordinary Lactic Acid 10% + HA (£5.80): Available at Asos, Beauty Bay, Cult Beauty, Feel Unique, Sephora, and Ulta

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Is The Inkey List Lactic Acid Serum a dupe for The Ordinary Lactic Acid 10% + HA?

Almost. The Inkey List Lactic Acid Serum and The Ordinary Lactic Acid 10% + HA are eerily similar and will give you the same results. But the former has a better texture and the latter the most practical packaging. The choice is yours.

The Inkey List Lactic Acid Serum Ingredients

Aqua (Water), Lactic Acid, Propanediol, Glycerin, Sodium Hydroxide, PPG-26-Buteth-26, Sodium Hyaluronate, Phenoxyethanol, PEG-40 Hydrogenated Castor Oil, Ethylhexylglycerin, Trisodium Ethylenediamine Disuccinate, Agastache Mexicana Flower/Leaf/Stem Extract.

The Ordinary Lactic Acid 10% + HA Ingredients

Aqua (Water), Lactic Acid, Glycerin, Pentylene Glycol, Propanediol, Sodium Hydroxide, Sodium Hyaluronate Crosspolymer, Tasmannia Lanceolata Fruit/Leaf Extract, Acacia Senegal Gum, Xanthan Gum, Isoceteth-20, Trisodium Ethylenediamine Disuccinate, Ethylhexylglycerin, 1,2-Hexanediol, Caprylyl Glycol.