Sunday Riley dupes on Amazon

The Ordinary Retinol 1% in Squalane ($9.90) for the Luna Retinol Sleeping Night Oil ($55), about 91% less per ounce. Same idea: a retinoid delivered overnight in a water-free oil that spreads thin and layers under a moisturizer.

Luna Retinol Sleeping Night Oil: The Ordinary Retinol 1% in Squalane, $9.90. Good Genes Lactic Acid Treatment: The Ordinary Lactic Acid 10% + HA, $9.20. Good Genes Lactic Acid Treatment: Naturium Multi-Bright Advanced Serum, $18. U.F.O. Ultra-Clarifying Acne Treatment Face Oil: e.l.f. SKIN PLZ Clarify Facial Oil, $9.17. C.E.O. 15% Vitamin C Brightening Serum: The Ordinary Ascorbyl Tetraisopalmitate Solution 20% in Vitamin F, $20.50. Auto Correct Brightening and Depuffing Eye Contour Cream: The INKEY List Caffeine Eye Cream, $14.

The cheaper alternatives here come from 4 brands: The Ordinary, for the Luna Retinol Sleeping Night Oil, Good Genes Lactic Acid Treatment, and C.E.O. 15% Vitamin C Brightening Serum; Naturium, for the Good Genes Lactic Acid Treatment; e.l.f. SKIN, for the U.F.O. Ultra-Clarifying Acne Treatment Face Oil; The INKEY List, for the Auto Correct Brightening and Depuffing Eye Contour Cream. Each is matched to the Sunday Riley product it stands in for on format, finish or key ingredients, and sold on Amazon by Amazon.com or its own brand.

That depends on the product. 5 of the 20 Sunday Riley products we track have a dupe sold by Amazon.com or the dupe's own brand, at a median 89% less per ounce. Bought together, the 5 originals come to $295 and their dupes to $62.77. Each comparison names what the cheaper one gives up. The other 15 have no dupe here yet, so for those the original is the only one we can point to.

C.E.O. Glow Vitamin C & Turmeric Face Oil, Aquamarine Melt Hydrating Gel-Balm Cleanser, C.E.O Tighten and Brighten Body Butter, C.E.O. Vitamin C Rich Hydration Cream, Juno Antioxidant and Superfood Face Oil, Pink Drink Skin Firming Resurfacing Essence, Blue Moon Cleansing Balm, Detox Darling Balancing Essence, C.E.O. Afterglow Brightening Vitamin C Gel, A+ High-Dose Retinol Serum, 5 Stars Retinol + Niacinamide Anti Aging Eye Serum, A.I. Adaptive Retinoid Serum, Breakout Breakup Salicylic Acid Cleanser, The Essentials: Good Genes All-In-One Lactic Acid Treatment, Peacekeeper Azaleic and Salicylic Acid Acne Treatment. A pair only goes up when the cheaper product matches on format, finish or key actives and is sold on Amazon US; nothing clears both bars yet.