Guides
The why behind the numbers
Every guide pairs with a calculator. Titles without a link are written next — listed so you can see where the site is going, not linked until they exist.
Soapmaking basics
The concepts behind every number the calculators print.
- Lye safety, start to finish Gloves, goggles, ventilation, and what to actually do if it splashes — the page to read before your first batch.
- Saponification explained What the lye is doing to the oil, why every oil needs a different amount, and where SAP values come from.
- Superfat explained: what % and why Why 5% is the default, when 8% or 20% is right, and what superfat does to lather and shelf life.
- Water discounting and lye concentration The three ways soapers describe water, why “38% of oils” misleads, and what concentration to pick.
- Trace: light, medium, thick What each stage looks like, which one each technique needs — and how much working time your recipe actually gives you.
- Gel phase: force it or prevent it What gel does to color and unmold time, why your mold decides whether it happens, and how to commit either way.
- Oil properties chart Hardness, cleansing, conditioning, bubbly and creamy for every oil in the calculator — sortable, filterable, printable.
- Your first cold process batch, step by step The classic beginner recipe, walked through with the calculator open — sized to your mold and your scale, not a blog’s.
- Cold process vs melt and pour vs hot process What each method asks of you, what it gives back — and what a bar costs by each route.
- How long soap needs to cure (and why) Water loss, hardness and mildness over four to six weeks — and the bars that need longer.
Troubleshooting
Symptom → cause → fix, in that order.
- Soda ash: causes and fixes The white film, why it isn’t the lye-heavy soap you fear, and the three mechanisms behind every prevention tip.
- Dreaded orange spots (DOS) Why iodine value is the wrong number, which oils actually invite rancidity, and how superfat and metals play in.
- Acceleration, ricing and seizing Four different failures that look alike in the pot, why no label can warn you, and a test that costs two grams.
- Soap too soft or won’t harden Recipe, water, cure or superfat — one measurement tells you which, and why “40% hard oils” is bad advice.
- How to test for lye-heavy soap Why pH strips can’t answer the question, how to zap-test safely, and how much free lye a bad batch actually holds.
- Air bubbles and glycerin rivers One is your stick blender, the other is your mold — and titanium dioxide only lets you see it.
Selling
Pricing, labeling and the numbers a tiny business runs on.
- Soap labeling rules: United States When soap is “soap” to the FDA and when it’s a cosmetic — what each label must say, and where MoCRA applies.
- Soap and cosmetic labeling: UK and EU There’s no soap exemption here: safety assessments, a Responsible Person, SCPN/CPNP notification — and the allergen list that tripled in July 2026.
- Insurance and legal basics for craft sellers What product liability costs per bar, what the policies cover, and why an LLC isn’t a substitute — sourced, and not legal advice.