Apply a few drops to face AM and PM.
Aqua (Water), Ascorbyl Glucoside, Propanediol, Aminomethyl Propanol, Triethanolamine, Isoceteth-20, Xanthan gum, Dimethyl Isosorbide, Ethoxydiglycol, Trisodium Ethylenediamine Disuccinate, 1,2-Hexanediol, Caprylyl Glycol.
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Yes, we are writing about Vitamin C while our top-selling Vitamin C formula has been (and is) out of stock for over a month. If that doesn't make sense, please refer to our name... but it's coming back really soon.
The Ordinary currently offers four Vitamin C formulations: Vitamin C Suspension 23% + HA (C23), Ascorbyl Glucoside Solution 12% (AG12), Ascorbyl Tetraisopalmitate Solution 20% in Vitamin F (ATS20) and Magnesium Ascorbyl Phosphate 10% (MAP10). We are about to introduce two additional Vitamin C formulations to make things worse: Vitamin C 30% Suspension in Silicone (C30) and 100% L-Ascorbic Acid Powder (C100), both really affordable and both coming in July.
Pure L-Ascorbic Acid (LAA) formulas (C23/C30/C100) are strongest but they sting as they are super potent. They are suspensions (since LAA is only soluble in water but it’s unstable in water) which means you must use tiny amounts per application to avoid balling up and product waste. C23 avoids silicones to maximize skin utilization of LAA and, as such, can feel a bit gritty despite the very fine mesh of LAA that we use. It can be mixed with hydrators to avoid this grittiness. C30 will include silicones to sting less and feel super smooth with no grittiness, but it will have slightly less skin utilization of LAA (which is why we included more LAA at 30%). C100 can be mixed with other formulas to incorporate LAA as you prefer.
What does this all mean? If you want easy, use AG12 (water base) or ATS20 (light oil base). They are less potent but user-friendly to fit any regimen. If you want maximum LAA exposure, use C23 (can mix with other formulas) or C30. If you are an expert, use C100 (mix the powder with other products in your regimen). If skin brightening is your key goal with Vitamin C, use MAP10. Ideally, don’t use LAA formulas at the same time as retinoids or peeling acids; alternate between AM and PM. (PS LAA is soluble only in water but oxidizes quickly in water which is why water formulations of LAA are simply never a good idea regardless of how they are packaged. They turn orange due to oxidation and some products mask this change in colour with added ingredients that are orange.)