This is the $10 serum Kim Kardashian swears by to keep her skin wrinkle-free

If Keeping Up With The Kardashians and every social media profile belonging to the stars of the reality TV show is anything to go by, it's a well-known fact that the Kardashian-Jenner clan are some of the most primped, preened and polished women to walk this earth. Almost every one of them has their own line of beauty products, and at any given moment you can bet that their contour kits or lip liners are doing the promotional circuit.

And now, ring-leader of the clan (or should I say klan), Kim Kardashian, has revealed what it is that keeps her skin looking so youthful. While it's rare to see the 37-year-old without makeup, you can tell that her skin is flawless. Always blemish-free and without a wrinkle in sight, we've been hungry for this knowledge for quite some time.

In a post on her website titled "How I slow the aging process", Kim listed all the products she uses on a regular basis. "In any skincare routine, anti-aging products are so important," the post reads. "They can have so many benefits, like reducing dark spots, preventing wrinkles, smoothing fine lines, and so much more."

But while we know Kim loves to splash out on expensive treatments like the infamous vampire facial, and despite the fact that she earns BOATLOADS of money (she made a cool $10 million on her first day of perfume sales for her Crystal Gardenia fragrances last year), her go to anti-wrinkle serum is actually surprisingly affordable. Heck, I'd even say it's cheap. 

One of the 15 products (15!) that she swears by is a retinol serum by British skincare brand The Ordinary. The product, a night serum that combines retinol (known for its anti-ageing benefits) with a gentler retinoid called hydroxypinacolone, is called Granactive Retinoid 2% Emulsion and retails at just $9.80.

The vegan, cruelty-free product uses the unique "next generation" retinoid to even out texture and dullness in the skin, as well as reduce signs of ageing, such as fine lines and wrinkles. The relatively low percentage of retinol also means that the irritation usually associated with pure retinol isn't an issue, and even people with sensitive skin can use the product.

Judging by the reviews on Sephora, where the product is currently sold, the product works wonders after only a few weeks. While Kim says she uses it mainly to fend off wrinkles, others use it to smoothen skin texture and to treat acne-prone skin.

And as you'd expect, among the other products Kim uses to "slow the ageing process" are some pricier goodies, such as Lancer Skincare’s Younger Revealing Face Mask Intense ($250), Drunk Elephant’s T.L.C. Sukari Babyfacial ($80), and Cover FX’s Anti-Aging Primer ($65).

Well, even if you can only afford the $10 retinoid emulsion from The Ordinary, it still counts as following Kim's top secret skincare regime, in my opinion. Let's just steer clear of those vampire facials...