Soap Recipe & Lye Calculator

Cold Process Saponification

Free · In‑App Purchases · Designed for iPad. Not verified for macOS.

Get the lye right every time. Add your oils and instantly see NaOH, water, and how your bar will feel — hardness, cleansing, lather. Offline. No subscription. Make soap with confidence. Soap Recipe & Lye Calculator does the one calculation every batch depends on — the exact lye — and shows you how the finished bar will turn out, before you pour. Add your oils and butters, and instantly see: • Precise lye (NaOH) and water for your batch, with your superfat and water settings • A live quality readout — hardness, cleansing, conditioning, bubbly & creamy lather, plus iodine and INS — so you can balance a recipe before you make it • Everything in grams, ounces, or percentages, with a library of 50 oils and butters Go further with a one-time Pro unlock: • Liquid soap (KOH) mode with lye purity • Fragrance & essential-oil calculator • Save and name unlimited recipes, with notes • Resize any batch to your mold • Export a clean, printable recipe sheet (PDF) to save or share Why makers like it: • Fast, beautiful, and works 100% offline — your recipes stay on your device • Trustworthy oil data, aligned to established soapmaking references (see Data & Sources) • One-time purchase. No subscription, no account, no clutter. SAFETY: Lye is caustic. Always wear gloves and eye protection, add lye to water (never water to lye), and make a small test batch — SAP values vary by oil source. This app is a formulation aid; safe handling is your responsibility.

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The developer, Ralf Pitter, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .

  • Data Not Linked to You

    The following data may be collected but it is not linked to your identity:

    • Usage Data

Privacy practices may vary, for example, based on the features you use or your age. Learn More

Accessibility

The developer has not yet indicated which accessibility features this app supports. Learn More

Information

Seller
Ralf Pitter
Size
30.7 MB
Category
Utilities
Compatibility
Requires iOS 13.0 or later.
  • iPhone
    Requires iOS 13.0 or later.
  • iPad
    Requires iPadOS 13.0 or later.
  • iPod touch
    Requires iOS 13.0 or later.
  • Mac
    Requires macOS 11.0 or later and a Mac with Apple M1 chip or later.
  • Apple Vision
    Requires visionOS 1.0 or later.
Languages
English
Age Rating
4+
In-App Purchases
Yes
Copyright
© 2026 Ralf Pitter
  • Developer Website
  • Privacy Policy

    • More by Ralf Pitter

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