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:
Print
Homemade Bar Dish Soap
- Prep Time: 45 minutes
- Total Time: 45 minutes
- Yield: 12 3.5 ounces bars 1x
- Category: soap
- Method: cold process
Description
A homemade bar soap that leaves dishes sparkling clean.
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
1. 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.
2. 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.
3. 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.
4. 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.
Notes
To calculate with a different volume, use these percentages:
96.67% coconut oil
3.33% castor oil
1% superfat
Keywords: zero waste dish washing, bar soap for dishes, homemade dish soap
Ashley says
Thank you for the detailed instruction. But I do have one question.
I’m finding that after my dishes and letting them air dry, I have a white water marks left behind. I thought it was because I wasn’t rinsing well enough. opps. but even after I rinse really well its still there.
If you have any insight on why this is happening – I would highly appreciate it.
Thank you
★★★★★
Kalie says
Can you melt this soap? I’d like to keep it in a bowl type dish by the sink but this recipe makes a lot from what I can tell. I thought it might be nice to make it into little bars I could just melt and pour into my dish as it empties.
Kimberly Denham says
Hi, I do love making soap! One suggestion is to pour this dish bar soap into bowls and let it dry. You would then use the bowl near your sink with a scrub brush. It would also be ready to gift easily! Thank you for your recipe.
Katie Shaw says
what a great idea! I’ll do that next time I make these!
Elizabeth Boyd says
Hello,
Want to know if I can use olive oil instead of coconut oil because I will soon not have access to coconut oil and olive oil is local to me. Also, how can I add essences to this? Thank you for publishing this!
Katie Shaw says
Elizabeth, the coconut oil makes for a hard, cleansing bar ideal for dishes. you can experiment with an olive oil bar but it will need a different amount of lye and will be your own custom recipe. you will need to go to a lye calculator to figure out how much lye you need. the thing about oliveoil soaps is they take a very, very long time to harden (months!). so it might not be ideal for you. as far as adding essential oils, you mix them in by hand after the oils and lye batter have formed a batter.
Anonymous says
Thank you so much for your help! If I am using the coconut oil, does it matter if I use extra virgin or not?
Katie Shaw says
no you don’t need that! in fact it would make these bars very expensive. look for one that’s non food grade, specifically for soap. I like this source: http://nurturesoap.com?aff=326
Jane Hemsteter says
Katie, Thank you for your recipe!
I do not know how to measure 5 2/5 oz
What would the amount I would read on my digital scale be?
Thank you
Jane
Katie Shaw says
hi Jane, I’m not sure where you are seeing that. here is the list of ingredients and measurements. maybe they are displaying differently on your screen>
1 ounce castor oil
29 ounces coconut oil
5.41 ounces of lye
8 to 11 ounces of water
1 tablespoon fragrance oil (optional)
kj says
Haven’t tried it yet but just made this according to the recipe. It looks super white and probably is very cleansing. I soaped at 85 degrees and it started cracking from getting too hot so I threw it in the freezer for an hour then in the fridge for a few hours. It’s going to be super hard so i’ll try to slice it in a few more hours. Excited to start washing my dishes with it!
★★★★
Tabitha says
Hi I wondered if there’s any way to blend this in a regular blender because I don’t have an immersion blender right now?
Thanks!
Katie Shaw says
sorry Tabitha 🙁 it would be really dangerous because the lye solution is so caustic. if it splattered it would harm you very badly. some people have had success whisking my hand, but it takes a long time and it’s never worked for me.
Pushpa Sellathurai says
Hi Katie. I would like to try your homemade bar dish soap recipe. However, being an Asian, my cooking involves lots of greasy utensils n cutlery. Eventhough high percentage of coconut oil is great for cutting down the oil, I m worried about my dry sensitive skin. How many percentage of olive oil (or any other suitable oil) should I add to the recipe or increase the superfat in order to make a less drying yet cleaning dish soap bar?
Katie Shaw says
I would try 60 coconut 40 olive and do a 2% superfat. Olive oil soaps have a very long cure time so give it a month before you use it! But it should still rinse clean and be very cleansing 🙂
Pushpa Sellathurai Muthiah says
Thank you for your prompt reply. Should I still add castor oil? If yes, how many percentage please?
Katie Shaw says
Yes, sorry! Do 60 coconut, 38 olive, 2 castor
No name says
Help! my soap won’t come to trace! Advice?
Skye Adams says
hi! i made this recipe several times and have loved it!- that being said I made it today and after I combined it and put it in the molds, it got REALLY hot. WAY hotter than usual… it also is kinda puffing up at the top. Advice? Any possible reasons why? Also, another batch I made cracked when they were curing (it might have been because something fell on it or other natural causes) but I wanted to know if I did something wrong. Thanks!
★★★★
Katie Shaw says
Hi Skye! It’s a hard soap so if it gets disturbed while its curing it will definitely crack! no worries, it will still work just fine. As far as as the hot batch, there are a few possible causes: 1. your ingredients were too hot when you blended (This will sometimes cause an overflow). 2. your soap got hot AFTER you poured it into the molds and it’s going through gel phase (looking translucent and getting super hot). this would happen if the room is warmer than usual, but typically would only only happen at 85 degrees or above. Either way, the final result should still be fine!
Stephanie Sullivan says
I made the soap and allowed it to cure. I am so excited to start using it. What do you do when soaking dishes? Do you use the same bar soap?
Katie Shaw says
hi Stephanie!
I just hold the bar under running water and let the pot fill up with bubbles
Ellie Rehl says
Hello there! I wanted to make this recipe in a loaf mold. Would it set up and dry out the same or would it mess up the recipe? Also, I love this blog! <3
Katie Shaw says
Hi Ellie, so it sets up SUPER hard and I think it would be too hard to cut! You could try it, but I just don’t know if you’ll be able to slice it into bars. Maybe if you cut it into it early? And thank you! 🙂
Ellie says
Thank you!!!!
Ellie says
Haha sorry one more question: have you ever used a circular mold or mini mason jars? Would those work? I’m just worried the mold used in the video might be too small or run out too quickly…thanks!
Katie Shaw says
I’ve never used a mini mason jar! it’s always nice to have a spare mold for an extra amount of soap that won’t fit in the mold. you can always just have a really small box lined with wax paper to catch any extra 🙂
Anonymous says
First I would like to thank you for giving us free recipient and taking the time to make videos and blogs. I truly appreciate it. I made this soap and find it a beautiful bar. Thank you again. I do have a question. My sink gets cloudy and certain pot as well. Not all pots. I’m Wondering if I did something wrong or maybe you can give me some advice on what could be the cause. Maybe my scale didn’t measure properly and I have too much oil or lye?
★★★★★
Katie Shaw says
hmm interesting… I’m not sure what the cause could be! is there a certain material that tends to not rinse clean? I’ve never had that problem, but I do use VERY hot water, which helps. the only thing I could think is maybe too much oil… there should be hardly any residue because the superfat is so low in this soap.
Anonymous says
I’m going to buy a new scale and remake the soap. Thank you for responding back so quickly.
Can the added essential oils at the end cause this? I don’t use fragrant oils.
Katie Shaw says
it’s possible! I used orange essential oil with no problem though! do you have hard water by the way?
Anonymous says
I couldn’t reply under your last response so I will respond here. No, I don’t have hard water. I used orange and lemongrass essential oil.
You bring up a good question. If there is hard water what would be the changes to make a dish soap for hard water?
Katie Shaw says
Just that hard water and bar soap can lead to soap scum, so you have to clean more often. This isn’t such a problem with detergents. One of the downsides of real soap.
Jenn says
You make this look so simple! I think this should be a goal of mine for 2020!
Jenn says
I think I really need to put soap making on my goals list for 2020! My oldest daughter is so interested in learning how! You make it look simple!
Elise says
Soap looks like so much fun to make! Thanks for the great tutorial!