Soap Calculator Comparison: SoapCalc, Brambleberry, SoapMaker 3 and More

TL;DR: The calculator is an essential tool - the differences in SAP values between them are small (1-2%), but each is suited to a different situation. Beginners: SoapCalc (free, complete). Sales: SoapMaker 3 (tracks costs and inventory). Quick verification: Brambleberry.

The soapmaking calculator is an essential tool for any soapmaker - it converts the weight of oils in a recipe into the exact amount of NaOH or KOH needed for saponification. But calculators vary in the accuracy of SAP values, availability of oils, ability to store recipes, and other features.

This page compares the most commonly used calculators available and helps you choose the right tool for your needs.

Why the choice of calculator matters — and when it doesn't

SAP numbers (saponification numbers) are chemical constants expressing how many grams of NaOH or KOH are needed to saponify 1 g of a particular oil. These values are measured experimentally and different calculators may use slightly different data sources.

The practical impact is small: a difference in SAP value of 1-2% for olive oil in a recipe of 500 g of oils means approximately 2-4 g difference in the amount of NaOH. This is a catchall for superfat - if you use SF 5%, a small difference between the calculators will not cause a problem. For the base oils (coconut, olive, sunflower) the SAP values are just consistent - only with more exotic ingredients do problems arise.

SoapCalc: the most popular free tool

URL: soapcalc.net/calc/SoapCalcWP.asp

SoapCalc is historically the most widely used free web-based calculator from the early 2000s - the de facto standard in the soapmaking community. It includes an extensive database of 100+ oils, displays predicted soap properties, and supports both NaOH and KOH without registration. But the user interface is outdated and features limited.

Strengths:

• Extensive oil database (100+ oils and fats)
• Display of predicted soap properties: hardness, cleansing, conditioning, bubbly, creamy, iodine, INS
• Support for NaOH and KOH
• Option to set super fat %
• Free, no registration
• Backward compatibility - recipes from 2010 still work today

Weaknesses:

• Outdated user interface (unchanged for about 15 years)
• No recipe storage (no registration)
• No mobile app
• No cost calculation
• SAP values from the database are not always updated with new oils

Predicted properties - explanation: SoapCalc displays a score of soap properties based on the fatty acid profile. These are Predictions, not guaranteed results. For example, the "conditioning“ score is based on the ratio of oleic acid, but does not take into account superfat or additives. Take as a guideline, not an exact description.

Recommendation: Ideal for NaOH/KOH calculation and fatty acid profile analysis. See detailed SoapCalc guide.

Brambleberry Lye Calculator: simple and mobile

URL: brambleberry.com/pages/lye-calculator

Brambleberry is a popular US supplier of ingredients with its own calculator - simpler than SoapCalc, but with a modern interface and mobile support. Quick calculation for simple recipes on a clear screen. Smaller database, but enough for basic oils.

Strengths:

• Clear modern UI, mobile friendly
• Calculation for NaOH and KOH
• Coverage of the most common oils
• Quick calculation for simple recipes

Weaknesses:

• Smaller oil database (approximately 50 oils)
• Does not display predicted soap properties
• No recipe storage
• Aimed at the US market - some EU-specific oils are missing
• Linked to Brambleberry products (marketing)

Recommendation: Suitable for quick calculation or as a verification of the result from SoapCalc.

SoapMaker 3: professional software with cost management

Type: Paid software (desktop applications, Windows)

SoapMaker 3 is a comprehensive software for professional and semi-professional makers - the only paid tool that is worthwhile if you make regularly. It manages recipes with version history, calculates the cost of each batch and keeps track of raw material inventory. Includes label printing and INCI calculation for sales.

Strengths:

• Recipe management with version history
• Calculating the cost of a recipe (you enter the prices of the ingredients, the software calculates the cost of the batch)
• Warehouse management (raw material inventory tracking)
• Oil database with editable SAP values
• Calculation of INCI composition
• Printing labels
• Batch tracking support

Weaknesses:

• Price: approx. 70-80 USD (one-time license)
• Windows only (no macOS or web version)
• Older software - development is slower
• Interface looks outdated
• For home makers, most of the functions are unnecessary

Recommendation: The investment is worthwhile if you produce regularly and need to keep track of costs, inventory and returns. For home or start-up producers, SoapCalc is sufficient.

Mobile apps: selection and risks

There are a number of mobile apps for calculating lye - the quality varies greatly. Look for a range of oil databases, the ability to save recipes, calculations for both NaOH and KOH and especially the currency of SAP values - check against SoapCalc.

Note: Some mobile apps have incorrect SAP values or round differently than web calculators. Always check the result on at least two sources until you know the behaviour of the app.

MMS Lye Calculator: legacy web standard

URL: thesage.com/calcs/lyecalc.html

The MMS Lye Calculator from Majestic Mountain Sage is one of the older web-based calculators, but still well maintained and functional. Similar to SoapCalc in database scope, without the registration. It is used by a smaller community, but the results are reliable.

Strengths:

• Large database of oils
• Clear display
• Free

Weaknesses:

• No recipe storage
• Legacy UI

Calculator comparison table

Validation of SAP values: comparison between calculators

For critical oils (coconut, olive, palm), SAP values are consistent across calculators. Problems arise for more exotic oils or for newer crops where the literature is less extensive. This comparison shows how consistent the base oils are:

Example SAP comparison for NaOH (g/g oil):

The values are consistent for these base oils. For specialty oils (baobab, marula, tamanu) it is advisable to check the SAP value in multiple calculators.

Recommended workflow for recipe calculation

1. Suggest a recipe in SoapCalc - oil percentages, set SF (recommended 5-8% for beginners).
2. Check predicted properties - ideal soap: hardness 29-54, cleansing 12-22, conditioning 44-69, bubbly 14-46, creamy 16-48, INS 136-165.
3. Verify the result in the second calculator (MMS or Brambleberry) - if NaOH differs by more than 2 g per 500 g of oils, find out the cause.
4. Add ingredients to the recipe (honey, clays, etc.) - the calculator only counts oils, additives are not reflected in the NaOH calculation.
5. Document the recipe - write down the resulting amounts of NaOH, oils and water for future batches.

Frequently asked questions

Which calculator is best for beginners? SoapCalc. It's free, contains everything you need, and is the most widely used - which means that when you run into a problem, you'll find the answer. The user interface is outdated but functional.

Do results differ between SoapCalc and Brambleberry? No. For base oils, SAP values are identical or vary by 1-2 g per 500 g of oil. Superfat absorbs this difference. Brombleberry does not have predicted properties, so SoapCalc will give you more information.

Is SoapMaker 3 worth buying? Yes, if (1) you produce regularly (at least 1-2 batches per month), (2) you want to track your prescription costs, (3) you want to easily manage your prescriptions and inventory. Not necessary for a home maker or hobbyist.

Can I calculate the recipe myself without a calculator? Technically, yes, but it's tedious and error-prone. The calculator eliminates mathematical errors and saves time.

How to choose a reliable FO or EO according to the calculator? The calculator does not sort on scents - both are calculated the same (percentage of oils). The difference is in the behavior during production (trace acceleration) and the stability of the scent - see the instructions for EO a FO.

What SAP number should I use if the sources are different? Source selection (SoapCalc, MMS) is not critical for base oils. The differences are in the superfat range. For exotic oils, choose a source that has the most recently published measurement (check the date), or use an average of several sources.

See also:

• SoapCalc Soap Calculator: guide - detailed Czech annotated guide
• Chemistry of saponification - why SAP numbers exist and what they mean
• Oil encyclopedia - SAP values for 19 oils with fatty acid profiles