Soaper - Soap Calculator

Soaper turns soap recipe math into tap-and-go simplicity — now on iPhone and iPad. Enter your oils, see instant lye calculations, and watch 10 quality metrics update in real time. No spreadsheets. No guessing. Just better soap.

Fully translated into 34 languages.
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WHAT YOU GET

Automatic lye calculations for NaOH (bar) and KOH (liquid) soap
10 quality metrics: hardness, lather type, gentleness, cure time, shelf life risk, and more
Auto Additives, Colorants and Fragrances — starting amounts scaled to your batch weight, with a tap to see where each number comes from
Fragrance safety warnings that flag blends pushing past skin-safe levels
Photos and documents — attach recipe shots, oil safety sheets, and supplier invoices to any item in your library
80+ oils with complete fatty acid profiles and saponification values
33 fragrances, 31 colorants, and 117 additives in the database
Three water calculation methods to match your preferred technique
Superfat control from 0% to whatever you like

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BLEND LAB
Not sure which oils to use? Blend Lab shows you.
Add oils and watch quality bars move in real time. Filter by chemistry—find oils that boost lather, improve hardness, or extend shelf life. The app suggests swaps to hit your target metrics without trial and error.
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BATCH TRACKING
Recipes are just the start. Soaper tracks your actual soap making across three process types: Cold Process, Hot Process, and Liquid Soap (KOH). Each has process-specific phases, timers, and educational content.
Beginner Mode: Step-by-step guided workflow with educational prompts.
Advanced Mode: Streamlined flow for experienced makers with condensed steps, timers, and batch notes.
Both modes include timers with notifications — step away and the app tells you when to come back. Track active batches, monitor cure progress, and log notes and photos.
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INVENTORY & SHOPPING
Know what you have. Know what you need.
Track on-hand quantities for every ingredient. Get low-stock alerts. Recipe availability shows which recipes you can make right now. The shopping list groups items by supplier with contact info and pricing notes.
Start a batch and ingredients deduct automatically. No manual math.
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QUALITY METRICS EXPLAINED
Soaper calculates 10 properties for every recipe:

Oil Balance Score — saturated vs unsaturated ratio
Foam Speed — how quickly lather forms
Skin Gentleness — moisturizing and conditioning
Fluffy Lather — big, airy bubbles
Creamy Lather — dense, stable foam
Set Speed — how fast the bar hardens
Bar Longevity — how long it lasts in the shower
Cure Time — estimated weeks until ready (4 weeks to 12 months depending on oils)
Lather Stability — bubble longevity from castor oil
Shelf Life Risk — DOS/rancidity warning for high-linoleic blends
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FREE VS PREMIUM
Free: Unlimited recipes, all 10 quality metrics, Blend Lab optimization, PDF export.
Premium ($2.99/month or $19.99/year): Guided batch flows, inventory management, shopping lists, supplier tracking, recipe cost estimates. Includes a 2-month free trial on annual plans.
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BUILT FOR SOAP MAKERS
Whether your first batch or your five hundredth, the chemistry stays consistent and the math stays invisible.