OUAI vs Kerastase (The Definitive Guide)

We're positive you've seen OUAI and Kerastase on the shelves at your local beauty store or hair salon before.

Which is better, you ask? That's what we'll be finding out today as we compare the two side-by-side. OUAI vs Kerastase - let’s get into it.

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OUAI vs Kerastase Shampoo & Conditioner

Before we dive in, it's important to acknowledge the diverse range of products offered by both OUAI and Kerastase. These two renowned brands have made their mark in the beauty industry with a wide array of hair care solutions, catering to practically every hair type and concern under the sun. From nourishing hair masks to styling serums, they've got it all.

However, for the purpose of this comparison, we're narrowing our focus to one of the most sought-after categories - volumizing products for fine hair. By comparing OUAI's Fine Hair Shampoo and Conditioner alongside Kerastase's Bain Volumifique and Gelée Volumifique, we aim to give you a snapshot of their approach to hair care excellence, which can be a window into their broader product lines.

So, all that’s left to address is which pair is right for you. Let’s take a closer look at both.

2024 update: Kerastase Gelée Volumifique (the conditioner) has been officially discontinued! The shampoo is still available, however, it seems like Kerastase are slowly lining up the Densifique Bain Densité and the Fondant Densité Conditioner as the successors to Volumifique.

Lightweight ingredients are the name of the game when it comes to fine hair formulas. So, Kerastase creates their wash day duo with their Amplifex System, which includes cellulose powder, cationic polymers, intra-cylane, and stylight texture. All these components work in tandem to tend to weak, fine strands without weighing them down. Thus, you can expect more volume, revitalized locks, and thicker-looking hair from root to tip.

OUAI’s Fine Hair Shampoo and Fine Hair Conditioner credit hydrolyzed keratin, strengthening biotin, and nourishing chia seed oil for pumping up the volume for fine tresses. (Not to mention, both are gluten free, paraben free, phthalate free and SLS free.) This combination promotes the look and feel of healthier hair by not completely stripping it of all its natural goodness while infusing featherlight moisturization.

Though both pairings work towards the same goal, they’re not created (see: priced) equally. OUAI’s are $30 each for a 10oz bottle, while Kerastase’s shampoo and conditioner are roughly $34 each for an 8.5oz and 6.8oz bottle, respectively. (Why couldn’t they just be the same size, Kerastase?!)

In my personal experience with both duos, Kerastase stood out for its immediate volumizing effect. Even with particularly fine hair, there was a noticeable difference in lift and thickness (without heaviness, I might add). However, if you're looking for products that nourish while adding volume, OUAI's formula might be the better choice. It left my hair feeling healthier, but with a lighter touch. Essentially, if your priority is instant volume, go for Kerastase; for a balance of nourishment and volume, OUAI is your one.

Even if your hair isn’t fine, volumizing formulas are a great addition to your haircare lineup. (After all, nobody’s looking to have flat, stiff tresses.) Bonus tip: combining these with a good dry shampoo or flipping your hair upside down for blow-drying can elevate your hair game significantly. But, let's pivot for a moment – shall we wrap up with some business ethics?

Packaging is at the forefront of Kerastase’s sustainability pledge, which is now made from 20%-95% recycled materials. They also offer refillable shampoo bottles and pouches for repeated reuse. They aim to replace more than 60% of their product packaging with recycled packaging by 2025 and have 100% of their plastic come from a recycled source by 2030. Though they claim to be cruelty-free, Cruelty-Free Kitty reports that they may test on animals via suppliers or third parties. And while they aren’t 100% vegan, they do offer some vegan options.

On the other hand, it doesn’t appear that OUAI has any sort of mission statement around sustainability or charity work. They do, however, offer refills for many of their shampoos, conditioners, and other solutions, which means less consumption of single-use plastic. (But if you do go the single-use plastic route, many of their bottles are recyclable!) According to Sephora, OUAI is also cruelty-free but not a fully vegan brand.

With all the essential details at your fingertips, from their commitment to clean beauty to the effectiveness and tangible results, you're now well-equipped to make an informed choice. Whichever pair you opt for, remember that the goal is to give your hair the opportunity to look and feel its best. Whether it's with OUAI or Kerastase, you're taking a step towards unlocking your hair's full potential.

OUAI Best-Sellers

For shine & damage protection:
Try the Hair Oil

For oily hair:
Try the Detox Shampoo

For perfect waves:
Try the Air Dry Foam

Kerastase Best-Sellers

For very damaged hair:
Try the Resistance Range

For color-treated hair:
Try the Reflection Range

For blonde hair:
Try the Blond Absolu Range

This article was originally published on November 18th 2022, but it has been reviewed and updated with the latest available information on February 14th 2024 by Sara Mckay, MA.