Sunday Riley Good Genes: Best Price on Amazon
The best-selling lactic acid treatment serum. The 1oz bottle is a meaningfully better per-ounce price than the 0.5oz trial size.
Category
Serum
Sizes on Amazon
2
Best price
1 fl oz
| Size | Price | Price / oz | ||
|---|---|---|---|---|
| 0.5 fl oz | $50.00 | $100.00/oz | Shop this size → | |
| 1 fl oz | $85.00 | $85.00/oz | Best Value | Shop this size → |
The best-value size saves about 15% per oz compared to the priciest size.
Prices and stock change on Amazon constantly, and we don't control them — the numbers above were checked directly against live listings in September 2026. Always confirm the current price before you buy; the size math (price per oz) is the durable part, not the exact dollar figures.
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