Sodium hydroxide vs potassium hydroxide for soap makers
When to use NaOH (bar soap) vs KOH (liquid soap), safety basics, and how to buy documented caustics in India.
Both sodium hydroxide (NaOH) and potassium hydroxide (KOH) are strong alkalis used to saponify oils. They are not interchangeable 1:1.
| NaOH | KOH | |
|---|---|---|
| Typical soap | Bar / hard soap | Liquid soap / cream soap |
| Common form | Flakes / pellets | Flakes |
| Handling | Corrosive, exothermic in water | Corrosive, hygroscopic |
Safety non-negotiables
- Always add caustic to water (controlled), never dump water onto a pile of caustic in an open vessel without procedure.
- Full PPE: goggles, gloves, long sleeves; see our NaOH safety guide.
- Calculate lye with a trusted soap calculator; verify oil masses.
Shop sodium hydroxide flakes and potassium hydroxide flakes, or start from the soap makers hub.
Frequently asked questions
Can I swap NaOH for KOH in a recipe?
Not without recalculating. They have different molecular weights and produce different soap textures.
Do you ship caustic safely?
Yes - sealed packs with SDS. Enter your pin code at checkout; follow all label and SDS instructions on receipt.
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