Get the Free Guide
Cold-Process Soap Atelier

You Already Know
Melt-and-Pour
Isn’t Enough.

Lather is a formulation atelier for women who want to understand cold-process chemistry — not just follow someone else’s recipe. Start with the free guide.

Scroll
Module 01 — Lye Safety

Fear of lye is the only thing between you and every soap you’ve ever wanted to make.

Sodium hydroxide is not dangerous when you understand it. Every professional soapmaker works with lye daily. The difference between fear and fluency is exactly twelve minutes of chemistry — and we cover it on Day One.

Saponification Value
190–205
NaOH per 100g oil

Every oil has a unique SAP value. You’ll calculate yours.

Lye Concentration
27–33%
water discount range

Lower water = harder bars, faster unmold. You choose.

Superfat Percentage
3–8%
excess oil range

Your skin-feel dial. We teach you what each number means.

Cross-section of a cold-process soap bar revealing peacock swirl pattern in deep teal and cream
Week 3 formulation — peacock swirl
Hands in nitrile gloves unmolding a fresh loaf of cold-process soap from a wooden slab mold
First unmold, first loaf
Overhead view of botanical soap ingredients — dried lavender, purple clay powder, shea butter, and sodium hydroxide measured in glass bowls
Measuring to the gram
Close-up of a beveled edge on a handmade soap bar with embedded rose petals and swirled terracotta clay
Beveled and labeled for market
Row of freshly cut cold-process soap bars curing on a wooden rack, cross-sections showing gradient swirls
Curing rack — Day 14
Artisan soap bars wrapped in kraft paper with handwritten labels on a linen surface at golden hour
Ready to ship
“I’d watched forty-seven YouTube tutorials. Lather was the first time someone explained why the lye calculation mattered — and I stopped being afraid.”
Headshot of Renata Voss, a woman in her late thirties with warm brown hair smiling
Renata Voss
Etsy seller → Cold-process formulator
The Curriculum

Fragrance oils are a shortcut. Essential oil blending is a skill.

Six modules. Each one designed so that by the end, you can pick up any oil, any botanical, and any colorant — and formulate something original without consulting a recipe.

01Foundation

Oil Chemistry & SAP Values

Why coconut oil produces a hard, cleansing bar while avocado oil adds creaminess. You’ll read a SAP chart the way a baker reads a hydration table.

02Chemistry

Lye Calculation by Hand

No app dependency. Pencil-and-paper formulation so you understand every gram.

03Scent Design

Essential Oil Blending

Fragrance oils are a shortcut. Blending essential oils for soap — accounting for acceleration and ricing — is a skill that takes your bars from commodity to craft.

04Color

Natural Colorants Lab

Brazilian purple clay, French green clay, madder root, activated charcoal — how to use each without morphing, bleeding, or fading.

05Design

Swirl Techniques

In-the-pot swirl, Taiwan swirl, drop swirl, hanger swirl. With tracing guides and pour-temperature charts.

06Business

Labeling for Legal Sale

FDA cosmetic labeling, INCI ingredient names, net weight declarations. Everything you need to sell at markets or ship subscription boxes.

Overhead flat-lay of a soap-making worktable with molds, a lye pitcher, glass measuring cups, a digital scale, and scattered dried botanicals on dark linen
6
Core modules
Chemistry through commerce
47+
Formulation exercises
Guided and freeform
15
Min. free masterclass
Lye safety — no email required first
Free Resources

Real chemistry knowledge, given away before we ask for anything.

The Cold-Process Starter Formulation Guide

A twelve-page PDF covering SAP values for fifteen common oils, a hand-calculation worksheet, and three beginner-safe formulations you can make this weekend — with full chemistry notes.

No spam. Unsubscribe whenever. Two fields, no friction.

Lye Safety Masterclass

15 min

A fifteen-minute video covering PPE setup, lye mixing sequence, temperature management, and the three mistakes that cause every soap-making accident — and how to never make them.

Gated behind email — same two fields
Student Work

They came in afraid of lye. They left selling at markets.

These are real formulations from real students — photographed by them, priced by them, sold by them. No recipes borrowed. No instructor’s batter poured on camera.

Student soap maker at a farmers market booth with rows of handmade cold-process soap bars labeled and priced on a wooden display
Priya Mehta
First market booth, 3 months after enrollment
Flat-lay of six handmade soap bars with distinct swirl patterns — lavender, charcoal, and oat — wrapped in kraft paper with handwritten INCI labels
Dana Kowalski
Original formulations, legally labeled
Close-up of a woman's hands cutting a fresh loaf of cold-process soap into bars with a soap cutter on a marble surface
Kezia Okonkwo
Moved from M&P to CP in six weeks
Subscription box of handmade cold-process soap bars nestled in kraft paper fill, ready for shipping with a handwritten note card
Margaux Delacroix
42-subscriber soap box launched
Artisan soap bars with embedded dried calendula flowers and a golden swirl, curing on a wooden rack in a bright studio
Tasha Brennan
Calendula & honey bar — bestseller
Overhead view of a student's soap formulation notebook open to a hand-calculated lye worksheet with annotated oil blend percentages
Sonja Lindqvist
Formulating without apps — Week 2
Row of colorful handmade soap bars displayed on a rustic wooden shelf at a craft market, each with a botanical garnish
Amara Osei
Craft fair debut — sold out

“I started because I wanted to stop buying from Etsy. I stayed because I couldn’t stop formulating. My first batch sold out at the neighborhood market in forty minutes.”

Portrait of Priya Mehta, a woman in her mid-thirties with dark hair and a bright smile
Priya Mehta
Lather student → Market vendor, Chicago

“The labeling module alone was worth the entire course. I’d been selling without proper INCI names for two years. Lather got me compliant in a weekend.”

Portrait of Dana Kowalski, a woman with blonde hair and blue eyes looking directly at camera
Dana Kowalski
Etsy seller → Compliant formulator, Portland

“I had sodium hydroxide in my cart for fourteen months before Lather. The lye safety module made me realize I’d been catastrophizing. I made my first batch three days later.”

Portrait of Kezia Okonkwo, a woman with natural hair and a warm expression
Kezia Okonkwo
Hobbyist → Cold-process soapmaker, Atlanta

“Forty-two subscribers in my soap box after three months. The formulation freedom this course gave me — I can design a scent, a color story, and a label from scratch. That’s a business.”

Portrait of Margaux Delacroix, a French-Canadian woman with short dark hair and an elegant expression
Margaux Delacroix
Lather graduate → Subscription box founder, Montreal

“I started because I wanted to stop buying from Etsy. I stayed because I couldn’t stop formulating. My first batch sold out at the neighborhood market in forty minutes.”

Portrait of Priya Mehta, a woman in her mid-thirties with dark hair and a bright smile
Priya Mehta
Lather student → Market vendor, Chicago

“The labeling module alone was worth the entire course. I’d been selling without proper INCI names for two years. Lather got me compliant in a weekend.”

Portrait of Dana Kowalski, a woman with blonde hair and blue eyes looking directly at camera
Dana Kowalski
Etsy seller → Compliant formulator, Portland

“I had sodium hydroxide in my cart for fourteen months before Lather. The lye safety module made me realize I’d been catastrophizing. I made my first batch three days later.”

Portrait of Kezia Okonkwo, a woman with natural hair and a warm expression
Kezia Okonkwo
Hobbyist → Cold-process soapmaker, Atlanta

“Forty-two subscribers in my soap box after three months. The formulation freedom this course gave me — I can design a scent, a color story, and a label from scratch. That’s a business.”

Portrait of Margaux Delacroix, a French-Canadian woman with short dark hair and an elegant expression
Margaux Delacroix
Lather graduate → Subscription box founder, Montreal
Ready to formulate?

Start with the free guide. No commitment.

Twelve pages of real chemistry. SAP values, calculation worksheets, three starter formulations. Yours immediately.

Send Me the Formulation Guide