The Soapmaker's Companion

The deep reference for soapmakers who want to understand the science behind the craft. Susan Miller Cavitch published this in 1997, and it remains the most thorough single volume on soap formulation available. Where Anne-Marie Faiola’s books focus on getting you started quickly, Cavitch’s book teaches you to think like a formulator.

Why Consider This One

“The Soapmaker’s Companion” is not the easiest first book, but it is the most educational. Cavitch explains the chemistry of saponification in accessible language, teaches you how to calculate your own lye ratios, and walks through the properties that different oils contribute to a finished bar. Once you absorb this material, you stop needing recipes entirely, because you can design bars from scratch.

The book covers over 40 recipes organized by type: basic bars, cream soaps, vegetable-based soaps, transparent soaps, and liquid soaps. It also includes guidance on troubleshooting common problems, adjusting formulas for specific skin types, and scaling recipes up for larger batches.

At 281 pages, it goes significantly deeper than most introductory books. The trade-off is that the presentation is more text-heavy and less visually guided. There are no step-by-step photographs. Cavitch relies on clear written instructions and diagrams instead. For some learners this is preferable, for others it makes the first batch feel more daunting.

This is the book to graduate to after you have made a few successful batches and want to understand why your soap behaves the way it does. Many experienced soapmakers consider it the single most important reference on their shelf.

What to Expect

A comprehensive, science-forward guide to soapmaking covering formulation, chemistry, and over 40 recipes across multiple soap types. At 281 pages, it is denser than the alternatives and assumes some basic familiarity with the craft. Best suited as a second book or for readers who prefer understanding the theory before starting.