Vegan Soap & Candle Math

What this book is

A project-based workbook for makers. Each chapter adds one number to a real market batch: how much oil the mold holds, how much lye those oils need, how much water, how the blend will behave, how much scent the rules allow, what a cured bar weighs, how much wax a jar takes, how much fragrance, how long the candle burns, and what it all costs and must sell for. The last chapter puts all twelve together into a make-day plan, a shopping list and a ledger.

What you build: the Market Batch. 12 melt-and-pour guest soaps to start; one palm-free cold-process loaf of 960 g of oils, 132.6 g of lye at a 5 % superfat, cut into 10 bars labeled 120 g (4.2 oz); and 12 soy candles in 70 mm jars, 245.8 g each, burning about 30 hours. Then the money: 1.88 a bar and 3.86 a candle in materials, and break-even at 4 batches a year at the book's example prices.

Who it is for: home-business makers who want cost per bar, price, profit and break-even for markets, online shops and wholesale; hobby soapers and chandlers who want to understand and check every lye, water, wax and wick number themselves; and vegan and palm-free makers, with plant oils and plant waxes only and how to spot animal and palm ingredients. Who it is not for: liquid-soap formulators, cosmetic chemists, and anyone looking for a safety assessment: the book does the arithmetic and points to the rules. Metric first, imperial beside it; every price illustrative and dated.

The book was written in collaboration with AI tools and reviewed by the author. Its numbers are checked by a verification program, and its figures are drawn by the same program, but mistakes may remain: see corrections & errata. Whatever this book or this site says, check every lye number in a lye calculator before you weigh.