Index / The Ordinary / EUK 134 0.1%
The Ordinary

EUK 134 0.1%.

The Ordinary EUK 134 0.1%

About this product

A serum formulated with EUK 134, a synthetic antioxidant intended to provide firming and antioxidant support.

Full ingredients

Propanediol, Ethylbisiminomethylguaiacol Manganese Chloride

Guru Score

76%

Yay

5 experts · Moderate agreement
5Gurus
3Yay
2Mixed
0Nay

What they liked

  • Inexpensive
  • Easy to incorporate
  • Firms and lifts at margins

What they flagged

  • Can't mix with acidic products
  • Requires careful product matching

What the gurus are saying

This serum needs careful pairing with other actives because it clashes with acids, but those willing to check their routine first find it offers subtle firming and antioxidant benefits. Experts split on the tradeoff: some find it an easy, inexpensive slot into everyday skincare, while others flag the mixing rules as worth the hassle for a more advanced formula.
Synthesized from 5 expert reviews · most recent take April 2026

What the gurus are saying.

Every take we've logged from this product's reviews across YouTube. Click any row to watch the moment they said it.

All takes Yay takes Nay takes Mixed takes Hide sponsored
Yay
"EUK 134 used to be really difficult to find, but then The Ordinary came out with their serum and kind of took all the stress out of it. It works on certain components of our skin to help tighten things at the margins. This isn't going to be a groundbreaking solution to jowls or increasing definition, but it will definitely help at the margins. And I think it's a really easy one to slot into your skincare routine to just dial up the results that you see. [...] I would recommend this every day of the year. Such a great product to include. And at the moment, [...] The Ordinary have their 23% off sale, which brings this down to about £7 here in the UK. So super inexpensive way of just getting a little extra firming and lifting action going in your skincare routine."
All 2 takes from Mad About Skin
Top 5 ULTIMATE SKIN FIRMING SERUMS - Best Anti Aging Routine Yet
"EUK 134 used to be really difficult to find, but then The Ordinary came out with their serum and kind of took all the stress out of it. It works on certain components of our skin to help tighten things at the margins. This isn't going to be a groundbreaking solution to jowls or increasing definition, but it will definitely help at the margins. And I think it's a really easy one to slot into your skincare routine to just dial up the results that you see. [...] I would recommend this every day of the year. Such a great product to include. And at the moment, [...] The Ordinary have their 23% off sale, which brings this down to about £7 here in the UK. So super inexpensive way of just getting a little extra firming and lifting action going in your skincare routine."
Top 5 SKIN FIRMING SERUMS - Lift Skin & Tighten Sagging Jowls
"One of my absolute favorite antioxidants for lifting and firming is The Ordinary EUK134. This is a super high potency antioxidant and works really well to preserve and protect collagen. It also has some great brightening benefits, too. So, it's a little bit of a double whammy that make it a bit of a no-brainer for an effective skincare routine. I absolutely love it and because it is quite high potency, some people do experience a little sensitivity with it, which I will call out. If you have more resilient skin, I think this would be a great option to go for if you have particularly sensitivity prone skin. Might not be the one for you, but is a fantastic fantastic option when it comes to preserving and protecting collagen."
Yay
"EUK 134 is by The Ordinary. This is one and the second is Resveratrol. Both EUK 134 and Resveratrol are ideal if you have dry sensitive skin and since you have dry sensitive skin you can even use it in the summer months."
All 2 takes from Nipun Kapur
Best Anti Aging For Dry Sensitive Skin | Nipun Kapur
"EUK 134 is by The Ordinary. This is one and the second is Resveratrol. Both EUK 134 and Resveratrol are ideal if you have dry sensitive skin and since you have dry sensitive skin you can even use it in the summer months."
Best Serums for Sensitive Skin | Nipun Kapur
"You can always try the EUK 134 again by The Ordinary. Skin combination skin slightly oily then I do recommend you try green tea serum as an alternate, green tea is a fabulous ingredient which is a natural antioxidant amazing but even if your skin is oily to combination it is going to work really really well."
Mixed
"There's a lot more ingredients that you don't want to mix it with, so definitely be aware if you do like lots of layers, lots of different steps in your routines, this may not be the right choice just based on how complicated it could be to add into that type of routine. I personally run into a lot of issues using this one. I have to really simplify my routine sometimes. It does feel a little stimulating on my personal sensitive skin, so I'm just putting that out there. I'm not saying that it is a harsh product, it's just if you have sensitive skin you got to be careful. If you're looking for the benefit of that antioxidant that gives that boost to your SPF in the morning and has some additional benefits for reducing some redness, maybe if you get very red in the sun, and also helps a little bit with just an overall brightness and evenness to the complexion, this would be the one to consider."
Yay
"The Ordinary EUK 134, this is a very highly potent antioxidant. Antioxidants help protect our skin from all the aggressors throughout the day. The aggressors cause these free radicals that cause skin damage, so we want to do in our anti-aging skincare routines everything that we can do to prevent free radical damage which causes aging. This is a very powerful one. If you want a very simple skincare routine, clean your skin, put a few drops of this on, and put your sunscreen on and you're good, literally that would be the simplest skin care routine that I can think of because antioxidants also help boost your sunscreen protection. It is one of the more powerful antioxidants out there, and those free radicals are cell damaging, and you want to do everything that you can to prevent cell damage to help slow down that cell damage and protect your skin."
Mixed
"The EUK from The Ordinary is one that I used to use in the past, not much anymore. It's a little bit finicky because it's hard to use. But she's like a little secret agent—she's got some tricks up her sleeves. The EUK can't be used with a lot of acidic products. You do have to be careful when adding it to a routine. I always need to like look at every single product and make sure that I know what I'm combining. But it's a wild card for a good reason, and it's related to that superoxide dismutase. If you want that in like a serum form, really, really good. They say that it's a mimetic of superoxide dismutase and catalase and that it's a regenerating molecule, so basically it refreshes itself. If you're looking for like a next level antioxidant, this is probably going to be it."

Frequently asked.

What is The Ordinary EUK 134 0.1%?

A serum formulated with EUK 134, a synthetic antioxidant intended to provide firming and antioxidant support.

Is The Ordinary EUK 134 0.1% worth it?

Mostly yes. 3 of the 5 gurus who reviewed it give it their stamp of approval, for a Guru Score of 76%.

What is The Ordinary EUK 134 0.1%'s Guru Score?

The Ordinary EUK 134 0.1% holds a Guru Score of 76%. That is our read on how warmly the experts talk about it, based on the verdicts of 5 expert reviewers we have collected.

Who is The Ordinary EUK 134 0.1% best for?

The Ordinary EUK 134 0.1% is generally suited to mature skin.

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