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Skin Rocks The Gentle Acid Versus Paula's Choice Skin Perfecting 6% Mandelic Acid + 2% Lactic Acid Liquid Exfoliant

Skin Rocks The Gentle Acid Versus Paula's Choice Skin Perfecting 6% Mandelic Acid + 2% Lactic Acid Liquid Exfoliant This smoothing toner is formulated around Mandelic Acid and Lactic Acid to refine skin texture and brighten dull-looking skin. This smoothing ex

Skin Rocks The Gentle Acid Versus Paula's Choice Skin Perfecting 6% Mandelic Acid + 2% Lactic Acid Liquid Exfoliant

This smoothing toner is formulated around Mandelic Acid and Lactic Acid to refine skin texture and brighten dull-looking skin.

This smoothing exfoliator is formulated around Mandelic Acid and Lactic Acid to refine skin texture and brighten dull-looking skin.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Sodium Hydroxide

Mandelic Acid

Lactic Acid

Pentylene Glycol

Glycerin

Ethoxydiglycol

Gluconolactone

Spondias Mombin Pulp Extract

Mangifera Indica Pulp Extract

Musa Sapientum Pulp Extract

Microcitrus Australasica Fruit Extract

Panthenol

Benzyl Alcohol

PPG-26-Buteth-26

Caprylhydroxamic Acid

PEG-40 Hydrogenated Castor Oil

Trisodium Ethylenediamine Disuccinate

Potassium Sorbate

Water, Sodium Hydroxide, Mandelic Acid, Lactic Acid, Pentylene Glycol, Glycerin, Ethoxydiglycol, Gluconolactone, Spondias Mombin Pulp Extract, Mangifera Indica Pulp Extract, Musa Sapientum Pulp Extract, Microcitrus Australasica Fruit Extract, Panthenol, Benzyl Alcohol, PPG-26-Buteth-26, Caprylhydroxamic Acid, PEG-40 Hydrogenated Castor Oil, Trisodium Ethylenediamine Disuccinate, Potassium Sorbate

2,3-Butanediol

Myrica Cerifera Fruit Extract

Akebia Quinata Stem Extract

Prunus Lannesiana Flower Extract

Lactobacillus Ferment Lysate

Saccharomyces Lysate

Achillea Millefolium Extract

Saccharide Isomerate

Arginine

Hydroxyacetophenone

Butylene Glycol

Sodium Phytate

Xanthan Gum

Citric Acid

Sodium Citrate

1,2-Hexanediol

Caprylyl Glycol

Sodium Benzoate

Water, 2,3-Butanediol, Mandelic Acid, Lactic Acid, Sodium Hydroxide, Myrica Cerifera Fruit Extract, Akebia Quinata Stem Extract, Prunus Lannesiana Flower Extract, Lactobacillus Ferment Lysate, Saccharomyces Lysate, Achillea Millefolium Extract, Saccharide Isomerate, Arginine, Hydroxyacetophenone, Butylene Glycol, Sodium Phytate, Pentylene Glycol, Xanthan Gum, Citric Acid, Sodium Citrate, 1,2-Hexanediol, Caprylyl Glycol, Sodium Benzoate

Reviews

Alternatives

Ingredients Explained

These ingredients are found in both products.

Ingredients higher up in an ingredient list are typically present in a larger amount.

Lactic Acid is another well-loved alpha hydroxy acid (AHA). It is gentler than glycolic acid but still highly effective.

Its main role is to exfoliate the surface of the skin by loosening the “glue” that holds dead skin cells together. Shedding those old cells leads to smoother, softer, and more even-toned skin.

Because lactic acid molecules are larger than glycolic acid, they don’t penetrate as deeply. This means they’re less likely to sting or irritate, making it a great choice for beginners or those with sensitive skin.

Like glycolic acid, it can:

Lactic acid also acts as a humectant (like hyaluronic acid). It can draw water into the skin to improve hydration and also plays a role in the skin's natural moisturizing factor (NMF) in the form of sodium lactate.

Studies show it can boost ceramide production to strengthen the skin barrier and even help balance the skin’s microbiome.

To get results, choose products with a pH between 3-4.

Lower strengths (5-12%) focus on surface exfoliation; higher strengths (12% and up) can reach deeper in the dermis (deeper, supportive layer) to improve skin texture and firmness over time.

Though it was originally derived from milk, most modern lactic acid used in skincare is vegan. It is made through non-dairy fermentation to create a bio-identical and stable form suitable for all formulations.

When lactic acid shows up near the end of an ingredient list, it usually means the brand added just a tiny amount to adjust the product’s pH.

Legend has it that Cleopatra used to bathe in sour milk to help reduce wrinkles.

Lactic acid is truly a gentle multitasker: it exfoliates, hydrates, strengthens, and brightens. It's a great ingredient for giving your skin a smooth, glowing, and healthy look without the harshness of stronger acids.

Read more about some other popular AHA's here:

Mandelic Acid is an alpha hydroxy acid (AHA).

Like other AHAs, it helps exfoliate the surface of the skin by breaking down the bonds that hold dead skin cells together. This helps reveal smoother and brighter skin underneath.

Mandelic acid helps with:

Due to it having a larger molecular size than glycolic acid, mandelic acid is able to penetrate the skin more slowly and evenly. This makes it gentler and less irritating, making it a great option for sensitive or beginner skin.

Despite being milder, mandelic acid is still an effective exfoliant that improves skin texture and tone over time.

What makes mandelic acid stand out from other AHAs? It has antibacterial and antioxidant properties.

These traits make it a great option for acne-prone or problem skin by reducing active breakouts and fading post-acne marks. Studies show that mandelic acid (especially when combined with salicylic acid) can significantly reduce pimples and hyperpigmentation while causing fewer side effects than stronger acids.

Mandelic acid is effective in concentrations of 5% and up with an ideal pH range of 3-4 for at-home use.

Like other AHAs, it’s important to wear sunscreen daily to protect your newly exfoliated skin.

However, unlike glycolic acid, mandelic acid is light-sensitive. Be sure your mandelic acid is packaged in opaque containers to ensure it stays stable and effective.

In short, mandelic acid is a gentle yet powerful AHA that exfoliates, brightens, and helps clarify skin while keeping irritation low. Its antibacterial action makes it especially beneficial for those with acne-prone, sensitive, or uneven skin, offering smoother, clearer, and more even-toned results over time.

Pentylene Glycol (1,2-pentanediol) is a multitasking little diol with three main roles in a formula:

Research on alkanediols (the family pentylene glycol belongs to) show they work by disrupting microbial cell membranes. This disruption helps the primary preservative system in a product work more effectively at lower doses.

On the safety side, the Cosmetic Ingredient Review Expert Panel has concluded this ingredient to be safe as used in current cosmetic practices + concentrations.

Typical use levels in a formula run about 1-5%.

Sodium Hydroxide is also known as lye or caustic soda. It is used to adjust the pH of products; many ingredients require a specific pH to be effective.

In small amounts, sodium hydroxide is considered safe to use. However, large amounts may cause chemical burns due to its high alkaline.

Your skin has a natural pH and acid mantle. This acid mantle helps prevent harmful bacteria from breaking through. The acid mantle also helps keep your skin hydrated.

"Alkaline" refers to a high pH level. A low pH level would be considered acidic.

Water. It's the most common cosmetic ingredient of all. You'll usually see it at the top of ingredient lists, meaning that it makes up the largest part of the product.

So why is it so popular? Water most often acts as a solvent - this means that it helps dissolve other ingredients into the formulation.

You'll also recognize water as that liquid we all need to stay alive. If you see this, drink a glass of water. Remember to stay hydrated!

Similar Comparisons

The reference edit

Ingredients, questions
& further reading.

Connected source records selected through this article’s public topic index.

01

Formula cabinet

Ingredients & structured notes

Ingredient index

Ingredients Side-by-side

  1. 01Water
  2. 02Methylpropanediol
  3. 03Butylene Glycol
  4. 04Salicylic Acid
  5. 05Polysorbate 20
  6. 06Camellia Oleifera Leaf
  7. 07Sodium Hydroxide
  8. 08Tetrasodium EDTA
  9. 09Water, Methylpropanediol, Butylene Glycol, Salicylic Acid, Polysorbate 20, Camellia Oleifera Leaf, Sodium Hydroxide, Tetrasodium EDTA
  10. 10Glycerin
  11. 11Sodium Laureth Sulfate
  12. 12Cellulose
  13. 13Lauryl Glucoside
  14. 14Acrylates/C10-30 Alkyl Acrylate Crosspolymer
  15. 15Microcrystalline Cellulose
  16. 16Phenoxyethanol
  17. 17Parfum
  18. 18Synthetic Wax
  19. 19Methylparaben
  20. 20Menthol
Source · skinsort.com
02

Product index

Related product references

Product

Paula's Choice BHA 9 Treatment

Paula's Choice BHA 9 Treatment Paula's Choice BHA 9 Treatment ingredients explained: Propylene Glycol⁠, PEG-75 Stearate⁠, PEG-8⁠, Water⁠, Salicylic Acid⁠, Glycerin⁠, Avena Sativa (Oat) Kern…

Source: incidecoder.comView reference →
03

Comparison edit

Read side by side