Calculate bar or liquid soap
Choose NaOH for solid soap or KOH for liquid soap, with cold-process and hot-process recipe settings.
Pocket Grove
SoapCraft: Soap Calculator
soap calculator app
Keep the soap math clear before you make the batch.
SoapCraft is a soap and lye calculator app for iPhone. Enter oils by weight or percentage, choose NaOH or KOH and a water method, then review the recipe totals and warnings in one focused workspace.
For iPhone. See the App Store for current availability and requirements.
Verified details
Know what you are downloading.
These details come from the current store listing and are shown here so people and search assistants can check the product before choosing a store.
- Platforms
- iPhone
- Price
- Free
- Category
- Utilities
- Requires
- iOS 18.0 or later
- Age rating
- 4+
- Version
- 1.1
- Size
- 10 MB
- Updated
- 19 July 2026
- Rating
- 5.0 out of 5 · 1 rating
For home soapmakers
Build, check, and keep a recipe without a cluttered workshop suite.
Use the water method you understand
Work with lye concentration, water-to-lye ratio, or water as a percentage of oils, with equivalent-water cross-checks.
Catch incomplete inputs
Visible warnings flag missing oils, percentages that do not total 100%, unusual superfat, invalid values, and settings worth checking.
Keep useful recipes
Save up to three recipes free, add notes and favourites, copy a plain-text summary, and resize or duplicate within the free limit.
How it works
Start with one decision. See where it takes you.
01
Set the recipe
Choose the process, lye type, units, oil input mode, superfat, fragrance, and water method.
02
Add the oils
Select oils from the built-in catalogue and enter percentages or weights.
03
Review the totals
Check lye, water, oil, additive, fragrance, yield, and full batch amounts alongside any warnings.
04
Save or share
Keep the recipe locally and copy or share its plain-text summary; Pro adds workshop, cure-tracking, and polished export tools.
Inside the app
App Store proof
5.0 / 5
Based on 1 App Store rating. Ratings are shown as Apple reports them.
Questions
About SoapCraft: Soap Calculator
What does SoapCraft calculate?
It calculates NaOH or KOH, water, oils, fragrance, additives, estimated yield, and total batch weight from the recipe inputs you provide.
Can it calculate both bar soap and liquid soap?
Yes. The current app supports NaOH recipes for solid soap and KOH recipes for liquid or paste soap, with cold-process and hot-process settings.
Which units and water methods are supported?
You can use grams, ounces, or pounds and choose lye concentration, water-to-lye ratio, or water as a percentage of oils.
What is included free?
The current listing includes the calculator, warnings, plain-text sharing, and up to three saved recipes free. Pro adds unlimited recipes, custom oils, full quality profiles, Make mode, cure tracking, and image or PDF exports.
Does a lye calculator certify that a recipe is safe?
No. SoapCraft performs calculations and highlights some unusual inputs, but it does not certify recipe safety or replace appropriate lye-handling guidance, accurate scales, supplier data, and protective equipment.
Ready when you are
Keep the soap math clear before you make the batch.
Download SoapCraft and keep the next soap recipe's numbers in one place.