Soap Making Oil Chart & Properties

How to Use This Chart

Click any column header to sort the entire list by that property. Want to find the oils with the highest lauric acid content? Click "Lauric." Want to know which oils produce the hardest bars? Sort by SAP value (higher SAP generally means a harder bar with more lather, but it's not the whole picture).

This chart shows the same oil data that powers the SoapCalc calculator. The difference is that here you can compare oils side by side, scan for patterns, and explore options before you commit to a recipe. The calculator tells you how much lye to use. This chart helps you decide which oils to use in the first place.

Understanding the Numbers

SAP Value (Saponification Value)

The SAP value tells you how much lye is needed to fully saponify a given oil. It's listed as both KOH and NaOH values. Higher SAP means the oil requires more lye per gram, which generally correlates with shorter carbon chains and harder, more cleansing soap. Coconut oil (SAP 0.257 KOH) needs a lot more lye than shea butter (0.179 KOH).

You don't need to memorize these. The calculator uses them automatically. But understanding SAP helps you make sense of why certain oil combinations work the way they do.

Iodine Value

Measures the degree of unsaturation in the oil. Lower iodine value = more saturated fat = harder bar of soap. Higher iodine = softer bar, more conditioning. Coconut oil has an iodine value around 10 (very hard). Olive oil is around 85 (much softer). This is the simplest way to predict whether an oil will make your bar harder or softer.

Oils with very high iodine values (above 140 or so) can produce soap that's prone to DOS — dreaded orange spots — because the unsaturated fatty acids oxidize over time. That doesn't mean you can't use them. It means you should keep them at a reasonable percentage and consider adding an antioxidant like rosemary oleoresin extract (ROE).

INS Value

Derived from the iodine and SAP values. An INS of around 160 is often cited as the "ideal" target for a balanced bar, but treat that as a rough guideline, not a rule. Plenty of excellent soaps have INS values well outside 160. 100% olive oil soap (Castile) has an INS around 105 and it's one of the most beloved soaps in history. Use INS as one data point among several, not as a pass/fail test.

Fatty Acids

Each fatty acid contributes specific qualities to your finished soap:

For a deeper look at how these fatty acids translate into the hardness, cleansing, conditioning, bubbly, and creamy scores in SoapCalc, see the Soap Qualities page.

Popular Oils for Soap Making

If you're staring at a list of 150 oils and don't know where to start, here are the ones most soap makers build their recipes around.

The workhorses

Coconut oil (76 deg) is in nearly every beginner recipe. High lauric acid means lots of lather and a hard bar. Most recipes use it at 20–30% of the total oil weight. Above 30–35% it can become drying.

Olive oil is the backbone of conditioning soap. High in oleic acid. Makes a gentle bar that's mild on sensitive skin. 100% olive oil soap (Castile) is soft and slow to trace but cures into something special if you wait 6+ months. Most recipes use olive at 25–50%.

Palm oil contributes palmitic and stearic acids — hardness and a creamy lather without the cleansing punch of coconut. Used at 20–30% in a lot of standard recipes. If you want to avoid palm oil for sustainability reasons, lard and tallow are the closest functional substitutes. Shea butter or cocoa butter can partially replace it too.

Lard and beef tallow make excellent soap. Tallow was the original soap fat for centuries. Both produce hard, creamy, long-lasting bars. If you render your own from a butcher or farm, the cost per pound is extremely low. They're functionally interchangeable with palm oil in most recipes.

The supporting cast

Castor oil is the lather booster. It's the only common soap oil with significant ricinoleic acid, which produces a thick, bubbly lather that makes other oils lather better too. Most recipes use 5–8%. More than 10% and the bar gets sticky.

Shea butter adds conditioning and a creamy feel. Doesn't contribute much to lather or hardness on its own, but it rounds out a recipe. Usually 5–10%.

Sweet almond oil, avocado oil, rice bran oil — all high in oleic acid, all conditioning. They're interchangeable in most recipes if you adjust with the calculator. Use them when you want a different feel than olive oil, or when one is cheaper than the others.

Palm Oil Alternatives

Palm oil is controversial because of its environmental impact — deforestation, habitat loss, labor practices. Some soap makers avoid it entirely. If that's you, here are the closest substitutes by function:

• Lard — The most direct substitute. Similar SAP, similar fatty acid profile, similar performance in soap. Swap 1:1.
• Beef tallow — Same story. Slightly different feel, equally effective. Swap 1:1.
• Cocoa butter — Adds hardness and stearic acid but behaves a bit differently at trace. Use at 15–20% max; higher amounts can cause cracking.
• Shea butter — Softer than palm. You'll need to compensate with more coconut or another hard oil. Not a 1:1 swap.

Whichever substitute you choose, recalculate with SoapCalc. Different oils have different SAP values, which means different lye amounts. Don't just swap oils in a recipe without running the numbers.