Soap Calculator FAQ

    Common questions about SoapMetrics

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    FAQ

    Soap calculator and lye calculator questions

    Direct answers about the free SoapMetrics soap calculator, lye calculations, oils, superfat, water, and the Premium workspace. For step-by-step calculator instructions, see the how to use the soap calculator guide. For batches, inventory, and cost tracking, see SoapMetrics as soap making software.

    Soap calculator questions

    Is the SoapMetrics soap calculator free, and do I need an account?

    Yes. The soap calculator, lye calculator, and recipe analysis are completely free, but a free account is required to use them. A free account also includes PDF export and live recipe notifications. Premium adds batch tracking, inventory, cost calculator, Ask SoapMetrics, and cure reminders on top.

    Does SoapMetrics work as a lye calculator?

    Yes. SoapMetrics calculates exact NaOH and KOH lye amounts for any recipe, including superfat, water ratio, and dual-lye/hybrid formulations — the same core math as a dedicated lye calculator, plus recipe and batch tools built around it.

    Can I calculate both NaOH and KOH soap recipes?

    Yes. The calculator supports sodium hydroxide (NaOH) for bar soap, potassium hydroxide (KOH) for liquid and paste soap, and hybrid dual-lye recipes, with purity, superfat, and water settings included in the formulation.

    Can SoapMetrics create dual-lye or hybrid recipes?

    Yes. Dual-lye (hybrid) mode calculates NaOH and KOH together so you can formulate recipes that use both alkalis. Measure each alkali separately using the calculated amounts.

    Is SoapMetrics only a soap calculator?

    No. The free calculator and lye calculator are the foundation, but SoapMetrics is also soap making software — recipe organization, batch tracking, inventory, cost calculator, and cure reminders for makers running more than one formula at a time. See how the pieces fit together on the soap making software page.

    Additional FAQ

    Can SoapMetrics help manage soap batches?

    Yes. Premium batch tracking records pour dates, cure progress, lot details, notes, recipe snapshots, and optional email reminders so production history stays attached to the formula you actually made.

    Can SoapMetrics manage soap-making inventory?

    Yes. Premium inventory tracking covers oils, additives, supplies, molds, suppliers, and completed bars so you can see what you have on hand before you formulate or pour.

    Does SoapMetrics have a soap cost calculator?

    Yes. Premium Cost Calculator imports the oils, lye, fragrance, additives, colorants, and toppings from your current recipe. You enter purchased quantity and price paid; SoapMetrics calculates what this recipe consumed and invested cost per bar. Distilled water is excluded by default. This worksheet is separate from Inventory.

    What is Ask SoapMetrics?

    Ask SoapMetrics is Premium recipe-aware AI help for the formula currently loaded in the Soap Calculator. It can assist with questions about trace, lather, softness, additives, and formulation. This is AI and it can make mistakes—always double-check answers before making soap. See the Ask SoapMetrics page for details and the disclaimer.

    Is SoapMetrics useful for a soap-making business?

    Yes. Hobby makers can stay on the free calculator, while serious artisans and small businesses can use the same platform to organize recipes, production, inventory, costs, and day-to-day batch records.

    How many oils are in the SoapMetrics database?

    151 records, of which 121 are currently available for new recipes. Each available oil, butter, fat, or wax carries NaOH/KOH SAP values and a fatty-acid profile used by the calculator. The remaining 30 records are held back from new-recipe selection while their material identity or saponification data is being verified; existing saved recipes that use them still load. A small number of available ingredients show bar-quality estimates as unavailable because their stored fatty-acid profile cannot support them.

    What's the difference between cold process and hot process soap in the calculator?

    Cold Process (CP) and Hot Process (HP) are the two soap-making process options in the calculator. CP is the default and uses a standard lye discount for superfat. HP enables post-cook superfat so selected oils can be added after the cook. Liquid soap is formulated with KOH (or dual-lye), not a separate process type.

    What superfat percentage should I use?

    Many body-bar recipes use 5–8% superfat. SoapMetrics treats 3–12% as a common range and flags values outside it. Hot process can also use post-cook superfat. Higher superfat is not automatically better — too much unsaponified oil can soften bars and affect lather.

    How is the water amount calculated (ratio vs. percentage)?

    SoapMetrics offers three water methods, and only one is active at a time. Water as % of oils is the default (38% of oil weight). Lye concentration sets alkali as a percent of the lye solution (commonly around 30%). Water:lye ratio sets liquid relative to lye by weight (commonly around 2.2:1).

    What are SAP values, and does the lye calculator use them?

    Yes. Each oil has sodium hydroxide (NaOH) and potassium hydroxide (KOH) saponification (SAP) values. SoapMetrics calculates lye from those SAP values, your oil weights, superfat, and lye purity — so changing oils changes the lye amount.