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INCI names / Lactic acid

Lactic acid INCI name

The INCI name for lactic acid is Lactic Acid. A lotion, balm or bath product lists it by that name. In cold-process soap it reacts with the lye and ends up as a lactate (sodium lactate, or potassium lactate with potassium hydroxide), so the tools list it as added and flag it for you to check.

In lotions, balms and other cosmeticsLactic Acid
In cold-process soapIt reacts with the lye and ends up as a lactate (sodium lactate, or potassium lactate with potassium hydroxide). The tools list it as added, "Lactic Acid", following Article 19(1)(g) of the Cosmetics Regulation ("at the time they are added"), and flag it for you to check. To name what the bar holds instead, add inci: with that name to the line.
On a US labelLactic Acid
In Great Britain and Northern IrelandThe same name as the EU. Northern Ireland uses the EU glossary cited below; Great Britain still uses the glossary it kept from the EU, where the name has another entry number.
What it is used for (CosIng)buffering, humectant, skin conditioning

Glossary citation: Lactic Acid #14271 (Commission Implementing Decision (EU) 2025/1175 on EUR-Lex).

In the soap or skincare tool, put it on its own line with its weight, for example "lactic acid, 5", and the tool prints the name for the region you choose.

Related

Transcribed from the EU glossary of common ingredient names (Implementing Decision (EU) 2025/1175) and checked against it; the US names are the ones FDA's substance registry (GSRS) records, and the uses are those CosIng, the Commission's cosmetic ingredient database, lists. A labelling reference.