can you halve recipes?

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Jun 8, 2017
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is it safe to just half all the ingredients in a soap recipe? Or will that throw the ratios out?
I agree with the others -- halve the fat weights and put these weights into a soap calc to figure the weight of NaOH or KOH and water. If you just halve the weights of all the ingredients, including the alkali, you will be introducing some rounding error. The error might not be a big deal, but it never hurts to be careful.

Since I get the impression you're using someone else's recipe, I want to also add that I always check every recipe in a soap calculator. I do this even if I'm not going to change the basic recipe even one tiny bit. Even the best of soapers can make mistakes, and there have been some big bloopers out there on the internet and in books. It's up to you to make sure you're using a safe and properly calculated recipe -- don't count on the original author to be right.
Yes, you can halve a recipe. Always a good idea to use the calculator!

A general rule is, if you have to round, round lye down and water and oil up.

Also consider your mixing container. if it is too big, your soap could be very shallow and splatter when you stick blend.
Always check using a lye calculator. And remember that you dont want to get too small (less than say 18 oz or half a kg) or else any measuring or rounding errors can potentially ruin the batch.
Every recipe has to be run through a soap calculator. Even if i want to make a smaller batch of one of my recipes. I have to run it through the calculator. That is how I do it with every recipe
You can use ratio and proportion to reduce the size of any recipe.
As has been stated there may be some rounding errors.
Then again, that's what a lye discount ( super fat) is for. It helps to make sure the resulting soap is safe to use and not too cleansing.
hi, can you help me with a recipe and downsize it. any new recipe i would like to make a min batch .

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