A simple recipe for cold process bar dish soap that gets your dishes sparkling clean. Add lemon fragrance for a fresh scent.
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Benefits of bar soap
Whether you are trying to live sustainably or live frugally, this bar dish soap will help you get there. Store bought dish soap is shockingly expensive and always comes in big plastic containers. But bar dish soap takes up hardly any room, is packaging free, and works just as well.
This recipe is almost all coconut oil, which is very cleansing but drying. I added a small amount of castor oil for extra lather, because everyone likes bubbles while washing the dishes. (For an even stronger soap, for use on laundry stains, you can try my homemade cleaning soap.)
If you want to add fragrance, you definitely can! Just keep in mind that this will be touching plates, where you eat your food. Because of that, I chose to use orange oil instead of a synthetic fragrance oil. If you want to use an essential oil, make sure you look for one that won’t fade as a the soap cures. (10x orange is a good one.)
It is calculated to a 1% superfat. This just means that there is very little extra moisture left over from the oils. They are almost all saponified, or turned into soap.
Because of the low superfat and high amount of coconut oil, this soap is not suitable for skin. But it leaves dishes sparkling clean! (Here is my best shower soap recipe.)
Basic Soapmaking Tips
🌿 If you have never tried homemade soap before, please see my beginner’s guide to cold process soap making, which will walk you through everything you need to know!
- Soapmaking can be dangerous and the ingredients deserve respect. Make sure you are wearing gloves, eye protection, and long sleeves. Any splashes can burn your skin or damage your eyesight. The fumes are also dangerous, so work in a well-ventilated area.
- Don’t make soap when you are rushed or stressed. Just don’t do it. You’ll make mistakes, and they are hard to undo.
- Keep all soap making ingredients away from children or pets. Anything with lye in it is dangerous until it has cured into a finished bar.
Ingredients and supplies you will need:
- 5.41 ounces of lye
- 29 ounces coconut oil
- 1 ounce castor oil
- Fragrance or essential oil, optional (I used 10x orange.)
- Individual bar soap mold that will hold a total of 45 ounces (I used two of these bar soap molds.)
- Stick blender
- Digital scale (I use this one with a percentage function.)
- Spare cups and a spare pot
- Safety goggles and gloves
Making Bar Dish Soap, Step by Step
Begin by measuring out the lye and water separately, using a digital scale. Combine them by adding the lye to the water (“snow floats on the lake”). Stir until the lye fully dissolves, and set aside in a safe place.
While the lye water is cooling, measure out the coconut oil and castor oil on the scale. They should technically be measured separately, but I just add them right to the pot I am melting them in.
Set the oils on the stove to melt on low, until they are fully melted and 140 degrees.
Now you need to wait for everything to cool down. This will take two to three hours. Both components should be about 100-110 degrees before you blend them together. Ideally, they will be close in temperature, less than ten degrees apart.
To blend, pour the lye water into the pot with the melted oils. Blend with your stick blender until a light trace is formed. That means that the blender leaves a trail (or “trace”) when it is dragged through the batter. You shouldn’t see any visible droplets of oil. It usually takes about 5 minutes of blending.
It will look like this
If you are adding fragrance, go ahead and do now and stir it in by hand.
Immediately pour into your soap molds and allow to harden for 24 hours before removing from the mold.
Let it cure for two weeks before using, otherwise it will dissolve too quickly.
Storage and use tips:
- Bar soap always lasts longer if it can dry in between uses. I use these soap savers to help air circulation.
- Don’t store your extra bars under sink. Put them in a dry closet or somewhere similar.
- To help clean your dishes, this works well with either a wooden scrub brush or a dish cloth.
- Again, don’t use as a hand soap, it’s too drying. But using it on your dishes won’t dry out your skin any more than a store-bought dishwashing liquid.
Print out the recipe here:
Homemade Bar Dish Soap
Ingredients
- 1 ounce castor oil
- 29 ounces coconut oil
- 5.41 ounces of lye
- 8 to 11 ounces of water
- 1 tablespoon fragrance oil optional
Instructions
- Measure the lye and water in separate containers, using a digital scale. Combine the lye and water by adding the lye to the water, then stir until dissolved. The lye solution will shoot up in temperature and become hot. Set aside to cool in a safe place.
- Measure the castor oil and coconut oil using a digital scale. Melt over low heat in a stainless steel pot until fully melted and 140 degrees. Set aside to cool in a safe place.
- When the lye water and melted oils have cooled to about 110 degrees, combine them by pouring the lye water into the melted oils. Blend with a stick blender until a thin trace is reached. (The mixture will thicken slightly and no droplets of oil are visible.) Add the fragrance, if using, and stir in by hand.
- Immediately pour into a soap mold with individual bars. (The soap dries too hard to cut easily if made as a loaf.). Remove from the molds after 24 hours and allow to cure 2 weeks more before using. Store the bar in a place that will allow it to dry as much as possible between uses.
Janelle Carriere says
Love it! Made our first batch and it turned out great!
I was wondering if this recipe is possible to do in a loaf mould? We did however and it seems to crack in the center, from what I understand it’s from overheating. Do you have any ideas on how to avoid this? Or are there any modifications we should make to the recipe to prevent this? I also read putting them in the fridge or freezer right after they’re poured might help. Any advice would be much appreciated!
Katie Shaw says
Yes, you absolutely can pop it in the fridge or freezer and that will help! (Just be aware its also hard to cut because it dries so hard) 🙂
Jenifer Lienau Thompson says
Hi Katie! Thanks for the recipe! I really love the idea of dish soap bars and have tried some commercial ones. The only drawback for me is having to chase the bar around the sink with my brush. I’m a potter, so my solution is to make small dishes into which I am planning to pour the soap to solidify and cure. I want to use it straight out of the dish. I’m planning to give these soap-filled dishes as gifts and wonder if you a can recommend dish soap a recipe I could make and send to recipients so they could melt and pour refills. Thanks for any advice!
Katie Shaw says
hi Jenifer, typically any cold process soap doesn’t melt all great a second time; you’d have to do something called a rebatch and it can get lumpy. can you just send them little filled dishes with a scrub brush?
Janet Hetzer says
Does it matter what kind of water I use? How much does this recipe make?
Katie Shaw says
any water is fine. I use tap water. it makes 12 bars using the molds I use. the total ounces varies a bit depending on how much water you use.
Sasha says
Hi thank you for this recipe! I have been looking for a dish soap recipe for a while and I can’t wait to try yours. I haven’t made soap in a long time so I’m sure this is a silly question but do I have to have a designated stick blender and pot for soap making or can I just use my same one that I use for cooking and clean well after? Thanks
Katie Shaw says
Sasha, yes you should have separate 🙂
Amanda says
What kind of lye are you using? The link is no longer working. Thanks.
Katie Shaw says
hi Amanda, sorry about that! Lately I’ve been using a kind that comes in micro-beads. its a little easier to pour and measure. here’s a link: https://amzn.to/3f0i3SV
June Eaton says
Hi I love your recipe however I think I need the percentage of lye to calculate it on Soapcal please 🙂
Katie Shaw says
this recipe is 1% superfat
Sirena says
Hello! Perhaps a silly question from someone who has only made soap once, but why do you give a range of ounces of water to be used? Should I just split the difference and use 9.5 oz water? Thanks 🙂
Katie Shaw says
not a silly question at all! so, yes I would recommend aiming towards the middle. less water will come to trace faster AND will cure and harden faster. it’s just personal preference. :).
mackenzie says
is there a shelf life on the dish soap? im planning to make a simple soap recipe with no essential oils
Katie Shaw says
Mackenzie, it will last AT LEAST a year in my experience. I just haven’t kept it longer than that so I can’t say for sure. But I think it would be fine for up to a couple years!
Hafsa says
I tried out this recipe. It is perfect.
Nancy says
I’ve made this twice. The first time it came to trace pretty quickly. This time, it’s close but not there. How long do you work at it? Can it be saved? I’m very careful in measuring. 🤷♀️
Katie Shaw says
hi Nancy! hmmmm. usually a difference in how long something is tracing has to do with the temperature of your oils or your room. if it’s traced, even if its very very thin, I would just pour into the molds and see how it does.
Kyersten says
Hating plastic and all the waste! Thanks for the recipe.
How do you use it for a sinkful of dishes? Grate it and add to water? Saturate cloth with it?
Katie Shaw says
I save my scraps and drop one in! Or I just hold it under running water.
Brian Mason says
I have some dish soap that I have used. Small pieces bad scraps that I can’t really use that well. Can I simply melt them in a pot and pour into the molds to make a new bar of soap?
Katie Shaw says
Brian, you can either save them and snap off a piece for throwing in the water when you’re soaking dishes or you can try to melt and re-pour. it comes out a bit lumpy. but if the appearance doesn’t matter much to you, it works!
Sharda says
Hello,
Can we make soap without lye..
Can we make from melt and pour method?
Katie Shaw says
yes of course you can do melt and pour! look for a 100% coconut oil soap base and add lemon essential oil.
irina banciu says
Hi have you tried adding vinegar or baking soda to the recipe to improve its cleaning power?
Stacey Carlson says
Would love to add vinegar and baking soda to a recipe…Do you have one you like?
Katie Shaw says
ladies I’d recommend getting soap flakes and mixing them with vinegar and baking soda. you can’t add them to a lye soap recipe because will react strangely. but they’d be great mixed with an already-made soap
Wendy carrillo says
I have a lot of body shower how do I turn it into bars of soap?
Katie Shaw says
I don’t think you can, sorry!
irina banciu says
can i replace castor oil with any other type of oil?
Katie Shaw says
its just for extra lather, you can substitute olive oil or simply leave it out. just run it through a lye calculator to make sure the lye value doesn’t change