Davines OI Oil dupe

BioSilk Silk Therapy Original Leave-In Treatment

−81%per oz

Davines · $57BioSilk · $13.74

Shared: Built the same way: a clear, water-free serum whose fast-evaporating carriers leave a film of dimethiconol on the hair for shine and frizz control.
The trade-off: Davines carries it in cyclopentasiloxane and disiloxane and adds roucou extract, sunflower oil and a sunscreen, octinoxate, while BioSilk uses a light isoalkane and isododecane with alcohol, panthenol and silk.
Sizes: 135 ml against 167 ml

OI Oil costs about $57 for 135 ml ($12.49 / fl oz). The dupe below is BioSilk Silk Therapy Original Leave-In Treatment at $13.74, about 81% less per ounce. Each pair is compared on format, finish and key ingredients, including what the dupe doesn't do.

Silicone shine oil for coarse, dry hair: volatile cyclopentasiloxane and disiloxane carry dimethiconol, which stays behind as a thin film against frizz, with roucou seed extract, sunflower oil, vitamin E and Davines' OI scent. 4.56 fl oz.

Amazon prices as of Sep 28, 2026, 1:12 AM ET, subject to change: the price on Amazon at checkout is the one that applies.

Buy the $13.74 dupe See the original

The dupe, side by side

The original

Davines

OI Oil

$57

$12.49 / fl oz

Cost per fl oz

Davines$12.49 / fl oz

BioSilk$2.43 / fl oz

$43.26 less at checkout than the original.

Size: Original · Davines135 ml; Dupe · BioSilk167 ml

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Questions

What is the best dupe for Davines OI Oil?

BioSilk Silk Therapy Original Leave-In Treatment at about $13.74. Built the same way: a clear, water-free serum whose fast-evaporating carriers leave a film of dimethiconol on the hair for shine and frizz control.

How much cheaper is BioSilk Silk Therapy Original Leave-In Treatment than OI Oil?

OI Oil costs about $57 for 135 ml, or $12.49 / fl oz. BioSilk Silk Therapy Original Leave-In Treatment works out at $2.43 / fl oz, roughly 81% less per ounce.

What does BioSilk Silk Therapy Original Leave-In Treatment do worse than OI Oil?

Davines carries it in cyclopentasiloxane and disiloxane and adds roucou extract, sunflower oil and a sunscreen, octinoxate, while BioSilk uses a light isoalkane and isododecane with alcohol, panthenol and silk.