Cold Process Soap Making for Beginners!

About 2 years ago I went on a skincare health kick. I don’t remember exactly what set it off, but it was probably after watching some doomsday documentary about the monsters living in our moisturizers. I’m pretty gullible when it comes to stuff like that, but I figure it’s better to be safe than sorry! I started off by cross-checking almost every bath & body product I was using on EWG’s Skin Deep Cosmetics Database. This is a great resource if you have a favorite product and want to know its potential hazard rating. I only felt comfortable using products with a rating lower than 4.  As helpful as this was, I started feeling less trusting of the companies behind the labels. The cosmetics industry does have certain standards to live up to, but you can never know for sure if a label is completely honest! I know this mindset can send me off the deep end where I move into a tree house and eat leaves for the rest of my life, so in the interest of REALISM, I decided to take on a new hobby: SOAP MAKING!

The idea of knowing exactly what was going into my most frequently used bath product was definitely appealing, to say the least. I set out on a mission to create a moisturizing, cleansing, fragrant, all natural soap with quality ingredients. It also doesn’t hurt that quality handmade soaps make WONDERFUL gifts!

There are a few different methods of soap making, but the one I ended up loving was Cold Process (CP). This method has a short prep time and a long cure time.  The cure time (4-6 weeks) is frustrating if you’re in a hurry to use your soap, but a long cure is necessary to produce the best quality. Making a batch of Cold Process Soap takes 1-2 hours initially and then an additional 4-6 weeks before you should use or gift it. This is how long it takes for the water to completely evaporate, resulting in a harder, longer lasting bar of soap. One misconception about CP cure time is that the soap is unsafe to use within the 4-6 week time frame because it hasn’t “saponified” yet. Saponification is the chemical reaction between fats, lye & water that produces the substance we call soap! It actually only takes about 2 days for saponification to complete. So technically, you can use your soap after 2 days, but it will be very soft and will most likely fall apart in the shower. “Aging” your soap is definitely encouraged! The long wait was annoying at first, but it allowed me to walk away from the project for a while, thus avoiding burnout (which I am 100% prone to) AND giving me something to look forward to!

Researching a topic like this can be extremely tedious, so I’m hoping to save budding CP soapers a little bit of trouble by consolidating everything I learned into this post. By the end, you will be equipped to try your first batch of CP soap!

A word of warning: CP soaping requires the use of lye (Sodium Hydroxide), which is a caustic substance that can cause severe burns if it’s inhaled or makes contact with skin. It’s EXTREMELY important to do all of your soap making in a well-ventilated room while using rubber gloves, goggles and a surgical mask. It’s also wise to wear long sleeves so that if any splashing occurs, your arms are protected.

In this giant tutorial I’ll be covering the following topics:

•    Supplies
•    Formulating Your Own Recipe
•    Beginner’s Test Recipe
•    Cold Process Instructions

Let’s get started!


Note: any supplies that make contact with lye should be devoted to soap making! Don’t use them for cooking once you’ve used them for soaping!

•    Rubber Gloves
•    Plastic Goggles
•    Surgical Mask
•    Stick Blender (aka Immersion Blender – you can get one of these for $20-$30)
•    Candy or Oil Thermometer
•    Tupperware Measuring Pitcher (with a lip for pouring, and a lid)
•    Heat-Proof Stirring Spoons
•    Measuring Cups & Measuring Spoons
•    1 Large Microwaveable Bowl
•    1 Small Bowl
•    Electric Scale that measures ounces and grams
•    Soap Mold(s) – you can order some cute ones from The Sage, one of my favorite suppliers!
Mold Tips:
– If you want a more rustic looking hand-cut bar of soap, purchase one of the “loaf” molds rather than the individual cavity molds. If you go the loaf route, you’ll need a sharp knife or soap cutting tool. I made my own loaf mold, if anyone wants a tutorial on this please let me know in the comments!
– If you don’t want to purchase a mold right away, just devote a 9×12 or 9×9 inch baking pan to soaping, and be sure to line it with parchment before pouring!
•    Parchment Paper (if you’re using a loaf mold)
•    Lye (Sodium Hydroxide) – you can order Sodium Hydroxide from a few places, but the prices do vary a bit depending on the location and the quality. Here is one of the best deals I could find: The Lye Guy
•    12 oz. Canola Oil (test recipe ingredient)
•    8 oz. Coconut Oil (test recipe ingredient) – You can get this in small quantities at the grocery store, but for larger quantities I order here, from the Fixed Oils section of You can find pretty much all of your Base Oils here.
•    8 oz. Olive Oil (test recipe ingredient)
•    1.6 oz. Orange Essential Oil (optional test recipe ingredient – use this if you want to scent & color your soap!) – I order mine here, from the Essential Oils section!

Formulating Your Own Recipe

Choosing Your Base Oils

CP soap is made by combining fats (base oils, aka fixed oils or carrier oils) and Lye Solution (Lye + a liquid of choice, we’ll use water for our test recipe). The Base Oils you choose will determine the qualities of your soap. For example, using Coconut Oil will produce a very bubbly, cleansing lather and a very hard bar of soap, but too much Coconut Oil will make your soap too drying. You’ll want to balance out the coconut with a more moisturizing base like Olive Oil. There are dozens of Base Oils to choose from, but understanding the chemical reaction that produces a quality soap can get complicated, so until we all earn our Ph.D.’s in chemistry, pre-made charts are our best friends! This chart is extremely helpful. It explains the fatty acid properties of Base Oils and what they each contribute to a bar of soap. They also recommend percentages of use in soap recipes. For example, next to Coconut Oil, they tell you not to use more than 30-35%, because using more than that will dry you out. You can compose an entire recipe using this chart! For our test recipe, I chose to use 42% Canola Oil, 29% Coconut Oil and 29% Olive Oil. This will produce a creamy, stable lather. I converted the percentages to ounces based on the capacity of the mold I’m using.

Calculating Your Lye Solution

Now that we’ve chosen our Base Oils, it’s time to calculate our Lye Solution. Again, I’m not a chemist, so I rely on a super handy Lye Calculator to do the hard work for me! There are a few out there, but I always use this one from You can save your recipes here, or just use this page to create your formula. I prefer to write everything down on paper but either way, make sure you record all your amounts.

First you’re going to select the unit of weight measurement (in our case, ounces), then choose the type of lye you’re using. For CP soap, you will always be using Sodium Hydroxide (NaOH). Next, enter your liquid of choice. We’ll be using water for our test recipe, but it’s possible to use other liquids such as goat’s milk, coffee, tea, etc. Further down the page you will see a list of Base Oils. Find your oils and enter the number of ounces you’ll be using next to each, then click “Calculate Lye”.

The next page will tell you how many ounces of water you need in your Lye Solution. They give a small range for the water amount, so I usually pick a number that falls in the middle of the range. On the right-hand side it will show the total weight of your oils and a chart with 2 columns: % excess fat and Lye Amount. Here is where you can choose how much you want to “superfat” your soap. Without superfatting, your Base Oils will be cancelled out by your Lye Solution during saponification. This means many of the moisturizing benefits of the oils you used won’t survive the chemical reaction. Superfatting is when your Base Oil to Lye Solution ratio is imbalanced just enough that a percentage of your oils will remain intact during saponification. This allows your soap to maintain the properties of those oils. If you go lower on the % excess fat column, you will have a dryer, harsher soap. If you go too high, your bar will be very moisturizing but it will also spoil faster because of the excess oil. I always stay between 5% and 7%. The number to the right of the % excess fat you choose shows exactly how many ounces of lye you need in your Lye Solution. Write down the water and lye amounts and that’s the formula for your Lye Solution based on the oils you entered.

Adding Scents, Colors & Exfoliants

These are the last ingredients to go into your soap. As you’re creating your own original recipes, always remember to write down the exact amounts of everything you’re using. When you create that magical batch of soap with the perfect color and scent, you really want to be able to replicate it! I can’t tell you how many times I rushed through a batch and miraculously nailed it, only to realize I never wrote down how much Cocoa Powder I used to get that delicious color! FRUSTRATING! Anyway, the theme here is natural, so for scenting my soaps I only use Essential Oils (EO). You can look into using Fragrance Oils but I’ve never worked with them in my recipes, so I can’t give a formula for those. The formula for Essential Oils goes roughly like this:

•    0.7 ounces per pound of Base Oils for most Essential Oils
•    0.9 ounces per pound of Base Oils for Citrus Oils
•    0.4 ounces per pound of Base Oils for more pervasive oils like mints and spices

The “per pound of Base Oils” is referring to the total weight of your oils. For our test recipe, the total weight is 28 ounces, or 1 lb. 12 oz. (16 oz. in a pound). If you make a batch and find the scent too weak or too strong using this formula, you can make slight adjustments for future batches.

For colors, keep it natural! Some great natural Colorants are dried ground herbs, clays, Essential Oils (like orange), cocoa powder and spices (be sure they’re not skin irritants!). When it comes to coloring your soap batch, you’ll have to do a bit of trial and error. There is no formula for this, so just have your Colorant on hand and be sure to write down the exact amount you end up using. Add Colorants with measuring cups or measuring spoons. This makes it easier to keep track of your amounts. Colors can change a bit during the curing process, so you can’t be sure how vibrant or dull your coloring will be until the 4-6 week cure time is over. This doesn’t really bother me though because the natural ingredients result in natural-looking tones and they don’t need to be very specific.

For Exfoliants you can add as much or as little as you want. Whenever I add Exfoliants like seeds or oatmeal, I go by how it looks and what I want the bar to be used for. For example, a foot massage bar would have a coarse Exfoliant in a high concentration. A more gentle body massage bar would have a finely ground Exfoliant at a lower concentration.

Beginner’s Test Recipe

Orange Olive Soap

Here’s a basic recipe with Base Oils you can get at the grocery store! To practice with the Lye Calculator, plug in the 3 Base Oil amounts and see how I got the water & lye amounts and total oil weight from the calculation page. Also see how I calculated the amount of Orange EO based on the total weight of the Base Oils:

Base Oils:
Canola Oil – 12 oz.
Coconut Oil – 8 oz.
Olive Oil – 8 oz.
Total Base Oil Weight: 28 oz. – or 1 lb. 12 oz. which means, since we’re using a Citrus Oil (referring back to the Essential Oils formulas, a Citrus Oil should be added at .9 oz. per pound of Base Oils) this recipe will call for about 1.6 oz. of Orange EO.

Lye Solution:
Water – 8.5 oz.
Lye – 3.99 oz.

Essential Oils (EO): (to add at trace – the stage of mixing where your soap reaches a thin pudding-like consistency)
Orange – 1.6 oz

Cold Process Instructions

There are 3 steps of preparation to complete before the curing process begins:

Step 1 – Making your Lye Solution & Melting Down your Base Oils

Get your measuring pitcher (with the lid nearby), put on rubber gloves, goggles & mask, and make sure you’re wearing long sleeves. Put the pitcher on a scale, and set the scale to 0 ounces. Add water until you reach the correct weight according to your recipe. Once the water is measured, reset the scale back to 0 ounces and slowly sprinkle the lye into the water until you reach the correct weight. The mixture will heat up rapidly to about 200 degrees F. Stir with a heat-proof spoon for a good 30 seconds so that the lye is fully dissolved and doesn’t cake up on the bottom of your pitcher. DON’T inhale directly over the pitcher, as the fumes can burn your throat & sinuses. Once you’ve stirred enough, put the lid on your pitcher and place it somewhere it can cool down safely. If you have kids or pets in the house, put the pitcher somewhere it won’t get knocked over. Check the solution with your thermometer about 30 minutes later by placing the probe in the center of the liquid. The temperature you’re looking for is between 100 and 125 degrees F. It can take anywhere from 30 minutes to 2 hours to reach this temp, depending on how much Lye Solution you’re working with.

While the Lye Solution is cooling, get a big microwaveable bowl and measure your Base Oils on the scale the same way you measured your Lye Solution. When you’re done measuring, melt down the oils in the microwave. Because a lot of the Base Oils you’ll use in CP soap will be solid at room temperature, the melting process can take up to 15 minutes. I usually just do 2 minutes at a time on high heat in the microwave, and stir to finish melting. You want to avoid over-heating the oils. Your Base Oil temperature should be between 100 and 125 degrees F when you mix it with the Lye Solution. Make sure the oils bowl has enough room for you to add in your Lye Solution and any other Essential Oils or Exfoliants.

While you’re waiting for your Base Oils and Lye Solution to finish cooling, line your mold with parchment paper or plastic wrap. Some molds don’t require lining before pouring, so check with the manufacturer of the mold you purchased.

Once your mold is lined, measure your Essential Oil(s) on the scale in a small bowl and set aside. This is also the time you’d want to prep any other additives you’re going to be using like oats, seeds, etc.

Step 2 – Combine the Base Oils, Lye Solution & Essential Oils/Colorants/Exfoliants and Pour

Once the Lye Solution and your Base Oil temperatures drop below 125 degrees F, slowly pour your Lye Solution into the bowl of melted oils. Mix with the stick blender on a low setting, keeping the blender near the bottom of the bowl.  You don’t want to splash the soap mixture out of the bowl, since saponification has not taken place yet and the solution is still caustic. The mixture will become cloudy and then start to thicken. After about 3-5 minutes of mixing, what you’re looking for is “trace” (pictured above on the right). This is when the solution reaches a runny pudding-like consistency. If you lift the blender out of the soap and it leaves marks on the surface, you’ve reached trace.

Now you’re ready to add your Essential Oils. Mix in the EO with the stick blender until it is fully incorporated, then add your Colorant and distribute evenly with the blender. In the Beginner’s Test Recipe, our Orange Oil will provide both scent and color, so you can skip adding a Colorant in this case. Lastly, add your Exfoliant (optional). If you’re using something like oats and you want the chunks to stay whole, you will want to stir them in by hand using a heat-proof spoon. If you’re using something tiny like seeds or ground oats, you can use the stick blender. Try to work quickly during these last steps because once trace has been reached, your mixture will be hardening more rapidly. Now you’re ready to pour.

Remember to keep track of the Colorant & Exfoliant amounts you end up using so that you can replicate the recipe later. Once the soap has been poured, you want to tap the bottom of your mold against the countertop to let any bubbles escape. Next, you can smooth the surface with the back of your spoon, cover the mold with plastic wrap and let it sit for 24 hours in a cool, dry place.

To clean your supplies, first rinse and wipe down the pitcher and spoon you used for the Lye Solution and set them someplace to dry. Then you can rinse and wipe down the rest of your bowls before the soap residue starts to harden. Once your bowls have been thoroughly rinsed you can run them through the dishwasher, but this isn’t really necessary since the soap residue you rinsed off cleaned the bowls.

Step 3 – De-Mold Your Soaps and Let Them Cure!

The next day you can de-mold the soaps and space them out on a cookie sheet to cure for at least 4 weeks. If you used a loaf mold, you need to cut the soaps before putting them on the cookie sheet. The more surface area of each bar is exposed, the better the cure will be. I usually put a label on the sheet with the recipe I used & the date I stored them so I don’t forget. Remember, a long cure means a top quality bar of soap!

Well that’s it! If you made it this far, CONGRATS and welcome to CP soaping! I look forward to hearing about your own soap-making endeavors! If you have any questions or anything to share, please leave a comment!

46 responses

  1. Great tutorial! I’ve thought about experimenting with soap-making, but I got overwhelmed trying to figure out the process. Where do you store your soap while it’s curing? Can it be stored pretty much anywhere? Also, yes, would love to see your DIY for the loaf mold!

    • Thank you!! I hope this makes it seem less scary 😀 I usually store the soap in a closet or cabinet where it’s out of the way, cool & dry! I’ll definitely get together a post about how to make your own soap mold. Soaping really is such a fun hobby, I hope you try it and love it as much as I do! 😀

  2. You had me at “I watched a scary documentary about soap, so I decided to make my own.” I’m more of an I-watched-a-scary-documentary-about-soap-and-muttered-‘someone-should-do-something-about-that’-then-took-a-shower type of guy.

  3. This is a wonderful tutorial- so well explained and with great resources, too. I’m starting to feel like soap-making is something I could actually try!

    I found your blog through craftgawker, btw 🙂 I love it so far; please keep adding recipes and diys.

  4. Thanks for the rcipe and tutorial it is a great one.I have been nervous about trying to make soap,now I think I wll try.

  5. Nice job on your site and instructions. I am a soap maker and think you did a great job. After you have been doing it awhile you will learn about discounting your water and then your soap will not be so soft and you can use it sooner. It is harder to do on the small batches you make, but for instance on my 9 lb batch today I used 20 oz lye and 30 oz water That percentage will work on any soap amount it is 1 and 1/2 times water as amount of lye. The sage recommends 36 to 54 oz of water for that recipe. So you can see it is quite a discount. Your soap will be much harder out of the mold. Just a tip, Nice job

  6. Hi Tiffany,
    Love your site, I am thinking of making soap to use in gift baskets I am making for Christmas. How did you know what your oz quantities were for your base oils to plug them into the lye calculator? Are those quantities the size bottles you have on hand of each?
    Thank you 🙂

    • Hi! Thank you! I’m so glad you’re enjoying the blog! 😀 To figure out the ratios of oils, I used this chart and then I scaled the amounts so that the total weight fit the capacity of my soap mold! In the section “Formulating Your Own Recipe” (in this blog post), you can find the details of how I chose my oils and amounts! 🙂 Christmas gift baskets of homemade soap are going to be a BIG hit!

  7. We have been making soap like this for a number of years, its lots of fun and the soap is wonderful, if you use it every day, it keeps mosquitoes and gnats from biting so much..the thing i learned quick is not to put your lye and water in a glass container.. i did the first time it got so hot it shattered…i almost had the big one..

    • What do you think they used in the old days to put the lye mixture in? They didn’t have plastic in the 1700s. Cast iron or heavy ceramic?

      • They used iron pots, but they also didn’t use the same kind of lye we use today. The chemical lye we use is much more concentrated so the tools and methods we use have more safety measures than they did back then. They used to make their own lye by running water over ash and collecting the remaining fluid. They would then mix this fluid with rendered animal fats and cook the mixture in a pot for several hours. The resulting soap was never very hard because this “lye fluid” wasn’t very strong, but it did produce a soft soap with sufficient cleansing properties!

    • For mixing my lye solutions, I use a glass coffee pot I purchased at a thrift shop. The handle is a must and I’ve never had a problem worrying about the glass. It’s perfect for the job!

  8. Can you make this without a stick blender? I’m currently living out of the US and a $20US stick blender ends up being closer to $50 here, which is a bit out of my budget. I’m guessing you could just use a wooden spoon and stir (a lot) during the saponification process like they did in the old days…right?

    • Glass isn’t safe because the lye can leave minuscule etchings on the glass. Over time, the glass becomes weaker until it breaks. That, and the possible temperature shock if you use ice cold/ frozen water, and dump the lye in all at once.

  9. Storage space is pretty tight in my house, so I’d like to make my bars in something I already have rather than buy a mold specific for the purpose. I was thinking muffin tins seemed about the right size, but I think it might be quite a bit of work to cut parchment paper to line them. Do you think the commercial paper liners would work, or would they just get stuck into the soap? Some of my muffin pans are silicone, would they work better?

    • Muffin papers should do just fine! They would work the same way parchment does, which is what I use. You can also use a rectangular (or square) baking pan lined with parchment and cut your bars by hand. Those would end up looking just like the ones cut from an official loaf mold. 🙂


  11. Thanks so much for this tutorial! Takes some of the “mystery” out of CP soap processing for me. I do wonder if it is OK for me to use my stick blender that I use for food or do I need one that is dedicated strickly for soap making? Thanks so much!

    • You’re welcome! 🙂 I’m so glad you found it helpful! The only problem with using your stick blender for both soap and cooking would be that because you start mixing before your oils have fully saponified, your mixer will be in contact with full strength essential oils that can be absorbed into the plastic of the mixer. Those flavors (of soap and oil) would then get into your food. It would be very hard to be sure you cleaned the mixer to the point that it wouldn’t affect the flavors of your food.

  12. I just finished reading your tutorial and I’m excited to get started, but could you explain how you coverted your percentages to ounces.

    • I just take the total capacity (in ounces) of my soap mold, and multiply it by my oil percentages. For example, if my loaf mold has a total capacity of 60 ounces, I would first subtract a few ounces to leave room for the lye solution and other additives, so lets say 50 ounces (you don’t have to do this if you don’t mind having a little extra soap mixture at the end). So with a total capacity of 50 ounces, let’s say my recipe called for 30% olive oil, 30% coconut oil and 40% palm oil. I would multiply 50 (ounces) x .30 (for 30%) to get my total for both the olive and coconut oils, which equals 18. Then I would multiply 50 (ounces) x .40 (for 40%) to get my total for the palm oil, which equals 24. Now I know I need 18 ounces of olive oil, 18 ounces of coconut oil, and 24 ounces of palm oil to fill my mold. When these numbers are added up, they equal 50, which is the total capacity I wanted to reach. I hope that made sense!! Enjoy creating your first batch of soap! 🙂

  13. Thank you SO much for a thorough, detailed tutorial! I have been reading/researching this process for weeks and I learned more from this one post than from all my other reading combined. Great job! Can’t wait to test your recipe out 🙂

    • I’m so glad you found this helpful!! I love to hear that because I had a really hard time gathering information when I was learning and I wanted to prevent others from going through the same thing! 🙂 Enjoy making your first batch of soap!!

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