New York Post may be compensated and/or receive an affiliate commission if you click or buy through our links. Featured pricing is subject to change.
If you’re on the hunt for a shampoo that actually delivers on its promises, the Redken Extreme Length Biotin Shampoo deserves a serious look.
I’ve been testing a lot of shampoos over the years — and as someone who writes about beauty products for a living, I try to keep my expectations grounded. But the Redken Extreme Length Biotin Shampoo, especially at its current price on Amazon, where the 33.8 fl oz jumbo bottle runs around $56, really surprised me.
For the volume you’re getting (roughly the size you’d expect from a full month or more of daily washing!), it’s an incredible value compared with many salon‑grade shampoos that cost just as much for half the size.
Redken Extreme Length Biotin Shampoo
AmazonOne thing I always have to mention when I review hair care products is my own hair type, because it really does affect how a shampoo performs. My hair is of medium thickness — not fine, not coarse — but where I struggle most is the ends. They tend to look a little wispy and undernourished, especially after heat styling.
I’ve noticed in the past that even shampoos that promise strength or length deliver more lather than actual results, so I approached this Redken Extreme Length formula with a healthy dose of skepticism.
The first thing that stood out to me about this shampoo is how gently it cleanses without stripping my hair. It has a pleasant, floral scent that isn’t overwhelming, and the texture feels nourishing rather than harsh. The bottle describes it as a biotin‑infused formula that strengthens damaged hair, prevents breakage and promotes healthy hair growth, and after several weeks of use, I can honestly say that my ends look more resilient and less frazzled.
I’ve also noticed real improvement in body, which is something I didn’t expect. Often strength‑focused shampoos can weigh hair down, but this one seems to build a subtle sense of fullness and bounce. When I blow‑dry without product, my hair still has movement and texture, not that flat, limp feel you get with lighter, clarifying shampoos.
What impresses me most is that I’m seeing these results without having to use a ton of product. A little goes a long way, so even though the bottle is already big, I imagine it will last me a long time. That’s a huge plus when you’re spending salon‑level money but hoping for performance that justifies it.
At the end of the day, for someone with hair similar to mine — medium‑thick with ends that could use some reinforcement and volume — this feels like a smart buy. The fact that you can get a jumbo size on Amazon for about $56 makes it feel like an even better deal, especially given the performance I’ve experienced.
So, if you’ve been chasing a shampoo that actually feels like it’s strengthening and adding life back into your strands, this Redken Extreme Length Biotin Shampoo is one worth trying.
more shampoos i love
After testing a boatload of clarifying shampoos, this drugstore option is one of the best.
I’m obsessed with Korean haircare and this is another option to help thicken strands.
For a salon-scented, luxe option, this premium shampoo is just shy of $50 (but Redken is a better value).
Why Trust Post Wanted by the New York Post
This article was written by Victoria McDonnell, New York Post Commerce Journalist & Content Strategist, who has spent countless hours researching, testing hundreds of products and comparing the latest makeup, skincare, hair and beauty items and trends to determine what’s truly worth your hard-earned cash. She evaluates formulas, textures, ingredients and more, in addition to consulting medical and industry experts. Some of Victoria’s latest conquests include testing the best sheet masks on the market, and a rinse-and-repeat review of the best shampoos for all hair types and budgets. Victoria, who received a beauty industry essentials certification from the Fashion Institute of Technology, has been creating shopping guides for the New York Post since 2021 and previously held positions at Insider Reviews and CNN Underscored.
Looking for a headline-worthy haul? Keep shopping Post Wanted.
