Multipurpose Soap Bar

Jump to recipe

This recipe is great if you have never made soap before. It is the same difficulty level as my basic soap bar for beginners, the only difference is that this soap bar has been formulated to be very hard, bubbly and cleansing. It’s perfect for household cleaning.

My other recipe is better suited for skincare – it is still bubbly, but it is softer and more moisturising. Whereas, this super cleansing and fragrance-free soap can be used for everything from washing dishes, laundry to bathing. Although I’ve recommended using my beginner soap bar recipe for your skincare, this soap bar is still perfectly safe to use on your skin – drying but safe.

If you’re not confident enough, you can always enrol in my soap-making course. Alternatively, you can sign-up to be notified when I host a soap-making workshop in your area. Before we lather up, let me deal with a few FAQs

Frequently Asked Questions

Is lye or caustic soda toxic and dangerous? Why is it in natural soap?

Yes, caustic soda / lye is dangerous. By itself, it should never come into contact with skin, eyes or your lungs…nothing besides your kitchen and bathroom drains! This is why you need to be extra careful when working with it in the soap making process. Unfortunately, it is absolutely necessary to make soap. The reaction between lye and oil is what causes saponification (i.e. soap). Most importantly:

Once lye reacts with oil it results in glycerine and soap, which is natural and completely safe. So the reaction looks something like this:

Oil + Base (lye solution) —–> Glycerol + Salt (soap).

For those of you that don’t know, “lye” is the term referred to when caustic soda is mixed with water (it is a solution).

What safety precautions must I take?
  1. Wear long sleeves to prevent any chemical burns if the mixture splashes.
  2. Wear safety gloves.
  3. Wear protective eyewear to protect your eyes from possible splashes.
  4. Do not touch, inhale or ingest caustic soda. Store it far out of reach of children and pets.
  5. When you add caustic soda to water (step 2 in recipe):
    1. Do it slowly.
    2. Always add caustic soda to water, and never the other way around.
    3. Do this step outdoors away from children and pets.
    4. Do not inhale or let the lye fumes get into your eyes.
    5. Do not touch the lye solution.
    6. Do not leave the solution unattended, because it will look like water.
    7. Be careful when carrying the solution back indoors, because the bowl will be very hot. So wear oven mits to carry the hot bowl, if necessary. Be careful not to trip. Walk slowly.
    8. It is safe to bring the solution back indoors when it becomes clear, like water, and the fumes have dissipated.
  6. If your skin comes into contact with the lye or soap mixture:
    1. Don't panic.
    2. Immediately wash the area thoroughly with cold water.
    3. Then wipe the area with white vinegar to neutralize the lye.

      If you do touch it, you will first feel an itch, which then starts to feel like a burn. When you feel the itch, rinse with water, and then vinegar.

  7. Have white vinegar around at all times. It will neutralize the lye. Wipe counter tops or whatever the mixture touches with vinegar.
  8. Before washing your utensils with dish washing soap, first rinse them with water and then wipe with a cloth that is soaked in white vinegar, or rinse in a vinegar solution (just fill the sink with water and add about a cup of vinegar – rinse in there). Then wash with dish washing liquid as usual.
Can I use the same pots that I eat from to make soap, or should I have separate equipment for soap-making?

You can use the same pots and equipment to cook and to make soap, but you must ensure that you clean everything properly and that all your equipment is stainless steel. I personally don't have separate equipment for soap-making, and I use the same pots to make soap and soup. I do have a separate blender though. It is obviously ideal if you can afford to have separate equipment, but it's not absolutely necessary.

How you must wash all your equipment before cooking with it after soap-making:

  1. Rinse all your equipment thoroughly in cold water;
  2. Then rinse or wipe your equipment in a vinegar solution to neutralize any lye (eg. fill the sink halfway with water and add about 1-2 cups of vinegar, or wipe with a cloth that is soaked in white vinegar);
  3. Then you can wash your equipment with dish washing liquid as you would normally wash your dishes. Now your equipment is ready to use for cooking.

A special note about blenders: Some blenders are not completely sealed where the blade compartment is, and they allow food to get stuck behind the blade etc. If your blender is not properly sealed, DO NOT use the same blender for cooking and soap-making. You will get soap in your soup.

Why can't I just buy natural soap?

Well, of course you can. The only reason to make your own soap is to save cost and customise, especially if you want organic soap (just make sure you use organic oils and additives). Just be cautious and always read the ingredients when you buy, as many retail soaps include unwanted and unnatural additives. This soap recipe only uses what is absolutely required to make soap, nothing added. All the rest is up to you.


This makes just over one litre of soap, which is roughly 10 bars. That’s enough to last one person six months or more!

This recipe has been formulated to be used for household cleaning purposes. It is a hard & bubbly bar of soap that will leave no greasy residue on dishes, clothes etc. In other words, it is not moisturising at all. However, it is technically safe to use for skincare, but it may be drying. If you are looking for a bubbly soap bar that is a bit softer and moisturising for your skin, I recommend using my basic soap bar recipe instead.

Cost & Shelf Life

Cost price: R6.97 per 100g soap bar.
Lasted me about: 1 month using every day for dishes (one bar).
Shelf life: 2 years if stored away from direct sunlight.

*Costs accurate at the time of writing, and based on the best retail prices I’ve found.


Long curing time: One week is not necessarily a long time, but when you’ve just made your first batch of soap, you will obviously be eager to try it out, so one week may seem like forever. This recipe uses the room temperature/ cold process method (CP), but if you’d like to cut the curing time substantially, then you may want to consider the hot process method (HP). This method requires you to be much more precise with temperatures, you need a crock pot/ slow cooker and the method is much longer (2 hours to the mould step), but the curing stage is much shorter. Whereas, the cold process method is quick (30 minutes to the mould step), but the curing stage is longer.


  • Customisable: You can completely customize this soap recipe. You add essential oils/ scents, colouring and textures according to your preferences.
  • Cost-effective: You can make organic soap in bulk, and save the cost of purchasing it all the time.
  • Many uses: This soap bar can be used as dish washing soap, laundry soap and as part of a laundry powder recipe. You can also melt it down to make a basic liquid soap.  Alternatively, you can learn how to make liquid soap from scratch.
  • Eco-friendly: this recipe contains only what you need, and is biodegradeable.

Recommended Retail Option

I highly recommend the multi-purpose soap bar made by The Bear Necessities, if you don’t have the time or interest in making soap. I have personally reviewed and approved their formula, and I can confidently say that their multi-purpose soap bar is the best retail substitute for my recipe. I also support The Bear Necessities, because they make every effort to reduce waste, and their handmade products contain safe and simple ingredients.

I‘d love to know what you use this multi-purpose soap bar for and how it works for you? Please share in the comments below.

6 thoughts on “Multipurpose Soap Bar”

    • Lemon juice is known to make soap seize, and if you add too much, the acidic nature of lemon juice will cause the soap reaction to occur backwards, because lemon juice will neutralise the lye and make it ineffective. In other words, your soap will turn back into oil. Even if it did technically work, you would still lose the beneficial properties and the natural fragrance of the lemons. Rather add dried lemon zest or lemon essential oil, but again, not too much. I recommend adding about 5ml lemon oil to every 1kg soap. Also, lemon essential oil’s fragrance has a reputation for fading. If you like the fresh fragrance, it would perhaps be better to use a fragrance oil (which is not natural), or an essential oil that has a similar fragrance profile like lemongrass or lemon verbena.

  1. I see you say you melt down this bar to make the liquid soap. But how is that done because in the recipe it calls for KOH instead of NaOH. I love your blog. Thank you

    • Hi Laura. Yes, to make a true liquid soap, you require KOH. When I suggest melting it down, that is to make a product that isn’t a true liquid soap, but functions as one. You can grate / chop soap bars and melt them over a low heat and then add an equal part (or less) of distilled water. The soap bar will dissolve, and you will be left with a diluted soap bar essentially, which works as a liquid soap for personal use for those who are not ready to tackle KOH yet. I have written more about this in another blog post: “How to make liquid soap from a soap bar”.

  2. I really appreciate your post it’s simple and understandable,I would like to ask if making soap for commercial purpose how long can one leave the soap to cure before sale when one has to meet up the demand

    • Hello Stella
      Thank you for your encouraging feedback about my posts. The minimum amount of time for a 100g soap bar is one week (for safety reasons), but the ideal amount of time in terms of soap quality (hardness and lather) is 6 weeks. Depending on the soap recipe, you can often get the hardness and lather quality sooner than that. For example, this multipurpose soap bar will be perfectly hard, bubbly and safe in 2 weeks, because it’s coconut oil based. Whereas, my beginner soap bar would need the full 6 weeks for best quality, because of the sunflower oil. And an olive oil soap would need 6 months for best quality! So it really depends on the recipe. All these soaps will be safe after 1 week, but not necessarily at an ideal quality. If you package too soon, they will be too soft and have poor lather. I hope that helps you.


Leave a Reply to Stella Jubomienye Cancel reply