Formulator - Lye Calculator icon

Formulator - Lye Calculator

An educational soapmaking calculator for NaOH/KOH lye math, oil weights, superfat, lye concentration, water, and safety-aware batch notes.

Public App Store price: $7.99 (one-time purchase).

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StatusLive

A focused soap math utility in the live Formulator slate.

Price$7.99

One-time App Store purchase for the standalone calculator.

Best ForBatch Checks

Verify lye, water, superfat, concentration, and assumptions before making the real batch.

Focused lye numbers, visible assumptions.
Soap math without theater

Focused lye numbers, visible assumptions.

Formulator - Lye Calculator keeps the dangerous part deliberately boring: SAP values, superfat, purity, lye concentration, water model, saved recipes, and a receipt you can audit before touching the real ingredients.

Product Visuals

Product visuals for the main workflow, with new shots added as each app settles into its launch clothes.

Phone calculator flow
Phone calculator flow
iPad calculation workspace
iPad calculation workspace

Current release-candidate screenshots for the calculator flow.

Why It Matters

If your batch math ever gets shaky, this gives you a faster check and a safer answer before you heat the lye.

SAP table

Use a multi-source oil table and manual SAP entries without flattening the real soapmaking catalog.

NaOH and KOH

Support hard bar soap and liquid or paste soap math with concentration and purity controls.

Safety-aware rounding

Round lye down and water up so the calculator is conservative where it should be.

Local saved recipes

Saved recipes stay on device, with no account, no tracking, and no network dependency.

Part Of The Lab

Use the calculator when the batch math matters. Bring the wider formula and packaging work into the rest of the Formulator family.

Wider Lab

Home Lab

Move from soap math into broader formulation workflows for soap, skin, hair, and ingredient review.

 Packaging

Label Forge Go

Turn batch and product details into label review and export prep when the formula is ready.

 Live Slate

All Apps

Browse the full app family, support pages, privacy policies, and current release status.

App Details

Platform, scope, support, privacy, and policy details in one place.

Platform
iOS
Release Track
Launch lane
Category
Utilities, Education, Lifestyle
Core Features
Oil catalog, manual SAP entry, NaOH/KOH selection, superfat controls, lye concentration, lye purity, water calculation, grams and ounces, and safety warnings.
Data Handling
Designed for local recipe calculations. Soap inputs, oil lists, batch sizes, notes, and calculation results remain on device unless the user chooses to export, share, or request support.
Use Scope
Soapmaking with sodium hydroxide or potassium hydroxide can be dangerous. Users must verify every recipe and follow proper safety practices.