Potassium Carbonate

AKA: 584-08-7, Dipotassium carbonate, Carbonate of potash, Anhydrous, Carbonic acid, Dipotassium salt, Pearl ash, Salt of tartar, Kaliumcarbonat, Kalium carbonicum
Synthetic
Clean
Potassium carbonate (K2CO3) is a white salt, soluble in water (insoluble in ethanol) which forms a strongly alkaline solution. It can be made as the product of potassium hydroxide's absorbent reaction with carbon dioxide. It presents a large capacity to absorb moisture.
Solubility Very soluble in water. Insoluble in ethanol
Formula
CK2O3
Mol. Weight
138.21
CAS #
584-08-7
Form
Powder
State
NKRA; Dry Powder, Liquid; Pellets or Large Crystals; Liquid; Dry Powder; Water or Solvent Wet Solid; Other Solid
Functions
Buffering
Stabilizes pH
Antioxidant Protection
Reduces Inflammation
Locks In Moisture
Traditional Use
Historically used in traditional soap-making for centuries across Europe and the Middle East, produced by burning plant ash (potash). Became a refined chemical ingredient in the 19th century for cosmetic pH buffering.
EWG
1
CIR
Safe as used
Pregnancy
Yes
CIR Safety Findings
medical-approval
all-shades-safe
Potential Sensitizer
Regulatory Status
USApermitted
EUrestricted
JAPANrestricted
CANADArestricted
Skin Types
all-skin-types
Best For
General
Pregnancy & Breastfeeding Safe
Yes
The paper trail
🔬Peer-reviewed1 paper
⚖️Regulatory1 listing
🛡️Safety-assessed2 reviews
Counts, not a verdict. A listing isn't a study. The trail, you decide.
Verified Jun 2026
Data: PubChem · CosIng · EWG · CIR