Keep this handy guide to acids in mind the next time you’re in the market for an effective exfoliating, hydrating, or anti-aging product.

The world of acids can be intimidating because there are so many to select from, and they all provide similar benefits. However, because each of them has variations, it's helpful to have a good understanding of what each common acid found in skin care accomplishes best. We've put together an all-in-one reference that delves into the most common acids found in skin care products, as well as what they may do for your skin.

Vitamin C (ascorbic acid)
You may be familiar with ascorbic acid as vitamin C, which is another name for it. Vitamin C is available in a variety of forms, with ascorbic acid serving as the gold standard. It has the greatest research behind it and offers a wide range of benefits. Because it is a powerful antioxidant, it aids in the slowing of the ageing process. Ascorbic acid also aids in the prevention of sun damage and can aid in the recovery of skin damage caused by UV exposure. It's also one of the most powerful ingredients for brightening and even out skin tone, as well as increasing firmness and suppleness by increasing collagen production.

The Ordinary Ascorbic Acid 8% + Alpha Arbutin 2% is one of our favourites. It includes 8 percent ascorbic acid and 2 percent Alpha Arbutin.

Glycolic Acid 
Glycolic acid belongs to the AHA (alpha hydroxy acid) family of exfoliants. As one of the most well-researched and efficient kinds of AHA, it is one of the most commonly used. Glycolic acid has a substantially lower molecular weight than some other AHAs, making it more effective at entering deeper into the skin. This provides a deeper exfoliation to remove dead skin cells and aid skin turnover, revealing youthful, fresh skin. Glycolic acid also improves the skin's capacity to retain moisture, making it one of the most moisturising acids on the market.

The Ordinary Glycolic Acid 7% Toning Solution is one of our favourites. It includes 7 percent of glycolic acid.

Hyaluronic Acid
This acid is so commonly used in skin care formulas because it really is just incredibly good. Hyaluronic acid can store 1,000 times its weight in water in its most efficient form, sodium hyaluronate. It doesn't only hydrate the skin, though. Hyaluronic acid also strengthens the skin by improving its moisture retention ability. 

Give your skin a major moisture boost with the The Ordinary Hyaluronic Acid 2% + B5, a serum that’s packed with several forms of the ingredient.

Lactic Acid 
Lactic acid is another type of AHA that helps to exfoliate the skin efficiently. Because of its bigger molecular structure, it operates at a surface level rather than entering deeper into the skin like other acid exfoliants. This implies it's more effective than other AHAs at smoothing and brightening skin while also being less sensitising.  Like glycolic acid, it can also help increase the skin’s moisture retention capabilities.

Try The Ordinary Lactic Acid 5% + Ha, which includes 5 percent lactic acid for a gentle yet effective exfoliation.  

PHAs (Polyhydroxy Acids)
PHAs are a favorite of those with sensitive skin as they provide many of the same exfoliating benefits as AHAs and BHAs, while being far gentler. They have a larger molecular size than AHAs, so their level of penetration is nowhere near as deep, but they can still exfoliate thoroughly at the surface.

You can find them in the Some By Mi AHA-BHA-PHA 30 Days Miracle Toner, which contains all three types of acids in small enough doses that the formula is still sensitive skin-friendly. 

Salicylic Acid
The most common form of BHA, or Beta Hydroxy Acid, is salicylic acid. BHAs provide a considerably deeper level of exfoliation than AHAs. BHAs, such as salicylic acid, exfoliate from within the pore, making them particularly useful for those suffering from acne, congestion, or textural problems.

If you have blackheads, the Cosrx Bha Blackhead Power Liquid is a salicylic acid-based liquid that deep cleans pores and controls sebum.