The Ordinary Mandelic Acid vs Lactic Acid

Chemical exfoliants are a great way to achieve glowing skin, as they remove dead skin cells that can make your skin look dull, clog pores, and cause breakouts. They can provide effective results without the harshness of physical scrubs.

Two popular chemical exfoliants are The Ordinary’s mandelic acid and lactic acid serums, both of which have unique benefits for your skin.

In this blog post, I’ll compare The Ordinary mandelic acid vs lactic acid serums so you can decide which one is best for your skin. I’ll compare their benefits in terms of effectiveness, skin type, pricing, and more.

This post contains affiliate links, and any purchases made through these links will result in a commission for me at no extra cost to you. Please read my Disclosure for additional information.

Key Differences Between Mandelic Acid and Lactic Acid

Before we look at The Ordinary products, let’s discuss the main differences between mandelic acid and lactic acid:

Mandelic acid and lactic acid are alpha hydroxy acids (AHAs) commonly used in skincare products for their exfoliating properties.

AHAs work by breaking down the bonds between dead skin cells, allowing them to be lifted away to reveal fresher, smoother, brighter skin.

Mandelic acid is derived from bitter almonds, while lactic acid, found naturally in our bodies, is derived from fermented plant and dairy products.

There are some key differences between the two:

Molecular Size and Depth of Penetration

Mandelic acid has a larger molecular size than lactic acid, which means it penetrates the skin more slowly and is less irritating.

Lactic acid, with its smaller molecular size, penetrates the skin more quickly, leading to more intense exfoliation.

Exfoliation Intensity

Lactic acid generally provides a stronger exfoliation than mandelic acid, making it more suitable for those looking for slightly better results in terms of skin texture and brightness.

Effect on Acne

Mandelic acid is known for its ability to improve mild to moderate acne thanks to its antibacterial and anti-inflammatory properties and the fact that it is both water- and oil-soluble.

Most other AHAs, including lactic acid, are water-soluble only, so mandelic acid has the added benefit of being able to enter into pores where pore-clogging sebum is produced.

When combined with salicylic acid, mandelic acid has also been shown to be effective at treating post-inflammatory scarring and hyperpigmentation.

Suitability For Different Skin Types

• Due to its gentler nature, mandelic acid is better suited for sensitive or reactive skin types. Mandelic acid also has properties that benefit oily, acne-prone skin.
• Lactic acid is more suitable for normal to dry skin types. It can provide a more potent exfoliation and benefit dry skin as it has moisturizing properties.

The Ordinary Mandelic Acid vs Lactic Acid

While The Ordinary offers two lactic acid serums, a 5% and a 10% concentration, they only offer one 10% mandelic acid serum.

So in this comparison, we’ll compare the same concentration serums: The Ordinary Mandelic Acid 10% + HA and The Ordinary Lactic Acid 10% + HA.

The formula also contains moisturizing glycerin and hyaluronic acid (HA) in the form of sodium hyaluronate crosspolymer.

This cross-linked form of hyaluronic acid is supposed to provide even better water-binding capabilities than HA.

Tasmannia lanceolata fruit/leaf extract, a natural antioxidant derived from the Tasmanian pepperberry, is included to help reduce skin irritation and redness.

Formulated for all skin types, this mandelic acid serum will provide a gentler exfoliation than some other AHAs (i.e., glycolic acid and lactic acid).

This is because, as previously mentioned, mandelic acid has a larger molecular size that penetrates the skin more slowly and not as deeply as glycolic acid and lactic acid. This makes mandelic acid a better choice for sensitive skin types.

Mandelic acid offers antibacterial and anti-inflammatory benefits, making it a good choice for those with oily and acne-prone skin and those with post-inflammatory hyperpigmentation and acne scars.

Like The Ordinary Mandelic Acid 10% + HA, this lactic acid serum also contains glycerin for added moisture, hydrating hyaluronic acid in the form of sodium hyaluronate crosspolymer for extended hydration and soothing Tasmannia lanceolata fruit/leaf extract.

Because of its smaller molecular size, lactic acid penetrates the skin more quickly and deeply than mandelic acid, which makes it more suitable for those looking for a slightly more intense exfoliation.

It targets uneven skin tone, dullness, and textural irregularities. The serum is ideal for dry skin types since lactic acid has moisturizing benefits.

Please note that if this serum is too strong for your skin, you can try The Ordinary Lactic Acid 5% + HA if you’d like a gentler exfoliation.

You read more about my experience with both The Ordinary lactic acid serums in this review post.

The Ordinary Mandelic Acid 10% + HA vs The Ordinary Lactic Acid 10% + HA

Similarities

Ingredients

Both The Ordinary Mandelic Acid and Lactic Acid serums contain a 10% concentration of their respective AHA and a 2% concentration of hyaluronic acid.

They also contain moisturizing glycerin and Tasmannia lanceolata fruit/leaf extract for its anti-inflammatory and soothing benefits.

Benefits

Both are water-based serums formulated to gently exfoliate the skin and sweep away dead skin cells for a brighter complexion and improved skin texture and tone.

Both are gentler on the skin than the smallest AHA, glycolic acid.

Differences

Skin Type

Mandelic Acid 10% + HA is better suited for sensitive skin types or those prone to redness, as it penetrates the skin more slowly. Mandelic Acid 10% + HA is also better suited to acne-prone skin types.

Lactic Acid 10% + HA is better for normal to dry skin types as it has moisturizing benefits.

Texture and Consistency

While both serums feel lightweight on my skin, Mandelic Acid 10% + HA has a silkier feel on my skin, while Lactic Acid 10% + HA has a more watery feel.

I’m guessing this silky feeling is due to the most concentrated ingredient in Mandelic Acid 10% + HA: propanediol.

Propanediol is a solvent and moisturizer with a somewhat oily feel upon application that dissipates once the product is absorbed. Lactic Acid 10% + HA also contains propanediol but in a lower concentration.

Lactic Acid 10% + HA has a pH of 3.60 – 3.80, while Mandelic Acid 10% + HA has a pH range of 3.50 – 4.50.

Exfoliation Strength and Effectiveness

Mandelic Acid 10% + HA is a gentler exfoliant compared to Lactic Acid 10% + HA, making it more suitable for those with sensitive skin types or who are just starting with AHA usage.

Lactic Acid 10% + HA is a slightly stronger exfoliant and will penetrate the skin faster and deeper.

Price

The Ordinary Lactic Acid 10% + HA is currently $8.90, while The Ordinary Mandelic Acid 10% + HA is $7.50.

How To Use The Ordinary Mandelic Acid and Lactic Acid Serums

Use Mandelic Acid 10% + HA OR Lactic Acid 10% + HA (do not use them at the same time) no more than once per day, preferably in the evening.

Apply after cleansing, before anhydrous serums, oils, suspensions, or creams.

The Ordinary notes that you can dilute the serums with other products to reduce their strength until your skin builds a tolerance.

When using exfoliating acids like AHAs and BHAs (beta hydroxy acids), be sure to use a broad-spectrum sunscreen with an SPF of 30 or higher during the day, as these types of acids make your skin more sensitive to the sun.

If you are just starting out with an exfoliating serum, use it once or twice a week and gradually increase usage as tolerated.

Don’t use the serums on sensitive, peeling, or compromised skin; avoid the eye contour and contact with your eyes. 

Be sure to patch test before using either serum for the first time to prevent an adverse initial reaction.

The Ordinary Mandelic Acid and Lactic Acid Serum Conflicts

Avoid using these The Ordinary serums at the same time as:

• Other Direct Acids/Exfoliating Acids
• Direct/Pure Vitamin C (Ascorbic Acid)
• Niacinamide Powder
• Peptides
• Copper Peptides
• Retinoids, including Retinol
• The Ordinary EUK 134 0.1%

Alternatives to The Ordinary Mandelic Acid and Lactic Acid Serums

If these lactic acid and mandelic acid serums are not the right fit for your skin, there are many other options if you want to add a chemical exfoliant to your skincare routine.

Here are a few affordable alternatives from The Ordinary:

Glycolic acid has the smallest molecule size of all AHAs, making it the most effective and powerful AHA.

Just remember that it may cause more irritation and dryness than mandelic acid or lactic acid, especially if you have sensitive skin.

This glycolic acid toner helps improve uneven skin tone, skin texture, and skin clarity. You apply it with a cotton pad to your face and neck.

Azelaic acid, an antioxidant derived from grains, helps brighten your skin and improve skin texture, typically with less irritation than other direct acids.

The suspension has a thick cream-like texture that can be used in both your morning and evening skincare routines.

Salicylic acid helps reduce acne and the look of enlarged pores by gently exfoliating away excess oil, bacteria, and dead skin cells while reducing visible redness.

Since the serum is water-based, it’s ideal for oily skin types. It’s even suitable for teenagers with mild to moderate acne.

The serum releases salicylic acid over time which helps reduce the risk of skin irritation, so if you have sensitive skin or are sensitive to salicylic acid, this could be a good option for you.

Related Post: How To Use The Ordinary Glycolic Acid

The Ordinary Mandelic Acid vs Lactic Acid: The Bottom Line

The Ordinary Mandelic Acid 10% + HA and The Ordinary Lactic Acid 10% + HA both offer effective, affordable exfoliation, but which is better will depend on your skin needs and skin type.

In general, Mandelic Acid 10% + HA will be better suited to those with acne-prone or sensitive skin, while Lactic Acid 10% + HA is better for drier skin types.

If you’re on the fence between the two, the serums are so affordable that you may want to try both to see what works better for you.

Regardless of which you choose, after using it at night, be prepared to wake to brighter, more refined skin with improved skin clarity.

For more details on these acids, be sure the check out my complete guide to The Ordinary acids.

Thanks for reading!