$0.99 local-first iPhone and iPad app

Lyestone

Soap lye calculator

Pick fats and grams. Get the exact lye. 43 saponifiable oils with literature-accurate NaOH and KOH SAP values, offline, no account.

What it does

Core utility

Calculate NaOH/KOH lye amounts, water settings, superfat, recipe quality scores, and CSV/Markdown exports.

Local by design

Recipes, fat selections, favorites, settings, and calculation history are stored locally in UserDefaults. No developer backend is included in version 1.0.

One-time purchase

$0.99 paid app. No subscription is required.