Ingredient Percentages: What You Need To Know – Skin Rocks

Ingredient Percentages: What You Need To Know

Bigger is always better, right? Wrong.

We know you want more bang for your buck, but are high-percentage actives more effective or just an excuse for brands to charge more? Let’s add up the numbers.

Is percentage chasing based on marketing or science?

I blame attention-seeking single-ingredient serums.

Marketers have got wise to our instinct that bigger is better, and the market is now flooded with high-percentage serums out to impress. Building a skincare routine can seem overwhelming, and number comparisons make it so much easier to choose.

They’ve sparked a war between marketers and formulators - and the marketers are winning. New products should be inspired by skincare innovation rather than a trendy ingredient with a good PR. 

Are high-percentage actives always more effective? 

No, not necessarily. Every ingredient has a recommended percentage regarding performance and safety, backed up by evidence formed by the manufacturer. 

I see a lot of ‘stealth sensitivity’ in my clinic. The use of too many high-percentage actives can overstimulate the skin and lead to breakouts and/or sensitivity – just not straight away. Your skin never forgets, and eventually, it will go on strike.

Many actives are just as effective at lower percentages, so you don’t have to pay more for a higher percentage and risk upsetting your skin barrier.

The delivery system and formulation are far more important than the percentage

Formulations are far more complex than one key ingredient: you need good quality, bioavailable* ingredients that can penetrate into your skin to work their magic. 

Suppose an overenthusiastic marketeer markets a 10% active serum. It will just loiter on the surface without a sophisticated delivery system. Your skin barrier is like a bouncer, and nothing gets in without an invitation. 

*bioavailable - The ability of a substance to be absorbed and used by the body.


Your barrier loves these super-effective, low-percentage actives:

(Please note: the percentages below are to be used a guide to indicate a comfortable yet effective range.)


Build up slowly if your skin is new to gold standard anti-ager vitamin A, or risk irritating your skin and peeling like crazy.

Retinyl Palmitate

A gentle soul – no need to worry about the percentage. Retinyl palmitate is like a starter bra and will help sensitive skin build up a tolerance to retinol, which is more like a plunge bra.


Percentage range: 0.01%- 2%

Easy does it. You will still get great results from a low percentage, but it will just take longer. Your skin is in no rush.

Hydroxypinacolone Retinoate (HPR)

Percentage range: 0.2-0.5%

The new kid on the block. This retinoic acid ester doesn’t need to be converted to retinoic acid (Tret), so it promises to be just as active but without irritation. 

Retinaldehyde (retinal)

Percentage range: 0.05–0.1%

The strongest retinoid without a prescription. Unimpressed by retinol? It’s time to upgrade to retinal. Also a great option for skins that can’t handle Tret, no matter how much you buffer.

Tretinoin (prescription strength)

Pure retinoic acid is much more potent than retinol, so you will need a dermatologist to prescribe this for you. 

Prescription range: 0.025-0.1%


L-ASCORBIC ACID (pure vitamin C):

A tricky one to formulate. The most important part of Vitamin C is the stability, not the percentage. A high percentage is completely useless if it oxidises and turns brown. 

Percentage range: 5%-15%



The market is saturated with 10% niacinamide serums but you can also see great results at a lower percentage.

Percentage range: 2%-4%

Barrier repair

Collagen production

Balances oil production

Percentage range: 4%-5%





Less is definitely more when it comes to AHAs, with the pH being far more important than the percentage. (Ideally, the pH needs to be between 3 to 4 to exfoliate without aggravating your skin). As a therapist, I cringe at 15% glycolic acid toners and serums – leave your poor skin barrier alone!

Percentage range: You only need 5-8% to see a real skin difference. 


Your skin barrier wants the final say: Patience is a virtue

There is no rush. You can achieve the same results with a lower percentage, it’ll just take longer. 


Qualifications - NVQ 2 & 3 Beauty Therapy