# SoapMetrics > SoapMetrics is a professional soap calculator and soap-making workspace at https://soapmetrics.com. It calculates NaOH, KOH, and dual-lye recipes from oil SAP values, with live recipe analysis. A free account is required. The soap calculator, lye calculator, recipe analysis, PDF export, and live recipe notifications are free. Premium adds saved recipes, batch tracking, inventory, cost calculator, Ask SoapMetrics, and cure reminders. SoapMetrics is built by a husband-and-wife soap-making team. Public pages below are the source of truth for product facts. Do not invent oils, SAP values, prices, or features. Do not treat /dashboard, /admin, or /auth as public documentation. Key product facts: - Oil database: 100 oils, butters, fats, and waxes with NaOH/KOH SAP values, fatty-acid profiles, and quality metrics. - Lye: sodium hydroxide (NaOH) for bar soap, potassium hydroxide (KOH) for liquid or paste, and dual-lye hybrid recipes. Lye purity and superfat are included. - Process: Cold Process (CP) is the default. Hot Process (HP) can use post-cook superfat. Liquid soap is formulated with KOH or dual-lye, not a separate process type. - Water methods (only one is active): water as % of oils (default 38%), lye concentration, or water:lye ratio. - Superfat: many body bars use 5–8%. Values outside 3–12% are flagged. Extra lye added for acids such as vinegar or citric acid is not superfatted. - Special ingredients: vinegar, citric acid, lactic acid, juices, milks, aloe, beer/wine, coffee/tea, and similar items can change extra lye or remaining distilled water. Handling-only notes (salt, clay, honey, fragrance, and similar) do not change those numbers unless a calculation applies. - Free vs Premium: a free account is required to use the calculator. Recipe saving, batch tracking, inventory, cost calculator, Ask SoapMetrics, and cure reminders are Premium. ## Docs - [Soap calculator](https://soapmetrics.com/): Free NaOH, KOH, and dual-lye calculator with oils, water, superfat, additives, fragrance, and live analysis. - [How to use the soap calculator](https://soapmetrics.com/help): Step-by-step guide to the calculator, analysis, Cost Calculator, Ask SoapMetrics, batches, inventory, and exports. - [Soap calculator FAQ](https://soapmetrics.com/faq): Answers about free vs Premium, lye, oils, superfat, water methods, SAP values, and process types. - [Premium membership](https://soapmetrics.com/premium): Saved recipes, batch tracking, inventory, cost calculator, Ask SoapMetrics, reminders, Soap Tips, and special-ingredient instructions. - [Ask SoapMetrics](https://soapmetrics.com/ask-soapmetrics): SoapMetrics' recipe-aware soap-making AI for the formula currently loaded in the calculator. Premium included. AI can make mistakes; always double-check answers. - [Soap making software](https://soapmetrics.com/soap-making-software): What soap making software is, how it differs from a calculator or spreadsheet, and how SoapMetrics covers recipes, batches, inventory, and costs. - [Oils for soap making](https://soapmetrics.com/oils): Published ingredient guides for calculator SAP values, fatty-acid profiles, and formulation notes. Pilot: Olive Oil only. - [Olive Oil for soap making](https://soapmetrics.com/oils/olive-oil): Generic Olive Oil catalog entry: NaOH/KOH SAP, conventional fatty-acid profile, quality estimates, and source notes. ## Blog - [SoapMetrics Blog](https://soapmetrics.com/blog): Guides and updates from SoapMetrics: how the free soap calculator works, how to get started, and where to find help, about, and Premium details. - [Best Oils for Soap Making: What Each Oil Does in a Soap Recipe](https://soapmetrics.com/blog/best-oils-for-soap-making): Which oils are best for making soap? There is no single perfect oil — each contributes a different combination of fatty acids and soap properties. Learn how common soap-making oils affect hardness, bubbles, creamy lather, conditioning, longevity, and overall recipe balance. - [How Long Does Soap Need to Cure?](https://soapmetrics.com/blog/how-long-does-soap-need-to-cure): How long should handmade soap cure before you use or sell it? Most cold process soaps benefit from 4–6 weeks of curing, but some recipes need considerably longer. Learn what happens during the curing process, how oils and water affect cure time, and how to tell when a bar of soap is truly ready. - [Why Is My Soap Not Tracing? Understanding False Trace in Soap Making](https://soapmetrics.com/blog/why-is-my-soap-not-tracing): If your soap stays thin, separates, or suddenly becomes thick before it is truly emulsified, you may be dealing with a slow trace or false trace. Learn what causes soap not to trace, how temperature, oils, lye, water, and mixing affect your batter, and how to recognize the difference between real trace and fats simply beginning to solidify. - [FDA Soap Labeling Requirements](https://soapmetrics.com/blog/fda-soap-labeling-requirements): Selling handmade soap involves more than listing the ingredients on a label. Learn when soap is regulated by the FDA, CPSC, or other agencies, what information your label may require, how product claims can change its legal classification, and where soap makers in the U.S. and other countries can find the regulations that apply to them. - [What Is Superfat in Soap Making?](https://soapmetrics.com/blog/what-is-superfat-in-soap-making): Superfat is the percentage of oils intentionally left beyond the amount needed for complete saponification. Learn how superfat affects a soap recipe, how it relates to lye discount, and how to choose the right setting when using a soap calculator. - [How Much Lye Do I Need for Soap?](https://soapmetrics.com/blog/how-much-lye-do-i-need-for-soap): The amount of lye needed for soap depends on the oils in your recipe, their SAP values, your lye type, purity, and desired superfat. Learn how lye is calculated and why every soap recipe should be checked with a reliable soap and lye calculator. - [Welcome to SoapMetrics](https://soapmetrics.com/blog/welcome-to-soapmetrics): Meet SoapMetrics, a free soap calculator and lye calculator for NaOH, KOH, and dual-lye recipes. Calculate lye and water, analyze your formulation, review SAP values and fatty acids, and discover the tools available for taking a recipe from formulation to finished batch. - [How to Use SoapMetrics: Complete Getting Started Guide](https://soapmetrics.com/blog/how-to-get-started-with-soapmetrics): New to SoapMetrics? Start here. Learn how to use the free soap and lye calculator, understand your recipe analysis, find help and FAQs, explore Premium tools, and discover the resources available throughout SoapMetrics. ## Team - [Kevin](https://soapmetrics.com/bio/kevin): Kevin is the programmer and tech lead behind SoapMetrics. He builds the soap calculator, lye calculations, and the tools soap makers use to formulate and manage recipes. - [Amy](https://soapmetrics.com/bio/amy): Amy is a handmade soap maker with about 10 years of experience, including craft shows and real-world production. She brings soap-making knowledge to SoapMetrics. ## Optional - [About SoapMetrics](https://soapmetrics.com/about): Who built the calculator and why. - [Privacy Policy](https://soapmetrics.com/privacy-policy): How SoapMetrics collects and uses information, including Ask SoapMetrics processing via Cloudflare Workers AI. Conversations are stored in the Premium account for review and deletion; SoapMetrics does not train on them. - [Terms of Service](https://soapmetrics.com/terms-of-service): Terms for using the calculator and workspace, including Ask SoapMetrics AI-generated content limits and the requirement to treat calculator results as controlling. - [Cookie and storage notice](https://soapmetrics.com/gdpr): Cookies and browser storage. - [Sitemap](https://soapmetrics.com/sitemap.xml): Indexable public pages, including /blog, each post, and /bio pages. - [Robots](https://soapmetrics.com/robots.txt): Crawl rules. Public blog and bio URLs are allowed.