How to Make Bath Bombs




I'm going to show you how to easily make bath bombs. I love to make them because they're super fun in the bath, and they can be quite beneficial for your skin too. You can customize this recipe with a few tweaks, that I will show you how to do in other instructables. To see more, you can visit my site

Lets start with the materials you need...

Step 1: Materials

 This is what you'll need:

- 4 ounces (114g) Baking Soda
- 2 ounces (57g) Citric Acid
- 2 ounces (57g) Corn Starch
- 2 ounces (57g) Epsom Salts

- 2 teaspoons Water
- 1/2 teaspoon Fragrance (I used orange)
- 1 tablespoon Oil ( I used Coconut Oil)
- 1 or 2 drops of food color (1 yellow and 1 red to get orange)

You will also need a mold to give your bath bombs a shape. I used an easter egg, but you can use any mold you want. 

Step 2: Method

 1. Start by weighing the dry ingredients. You should always measure by weigh when making bath bombs. I weigh in the following order: baking soda, citric acid, corn starch, then epsom salts. They weigh 10 ounces (284g) combined. You can weigh them one by one or together. As you can see by the picture sequence, I weighed them together. 

2. Once you have weighed the dry ingredients, put them in a plastic or crystal bowl and set aside.

3. Now measure your wet ingredients and mix them all in a plastic or glass bowl. They won't mix perfectly, don't worry about that. You should have a little less that 2 tablespoons total of wet ingredients. Maybe you won't need that entire amount. Depends on the weather that day. If it's raining you'll need less moisture. But more on that later. 

4. Start adding the wet ingredients to the dry mix one teaspoon at a time. Don't add more than that amount at once because the mix will start reacting. Whisk the mix at the same time you're adding the liquid. 

5. When you have added two teaspoons, test your mix by pinching a little bit in your hand. If it stays together and feels damp, your mix is ready. But if falls apart, keep adding liquid, 1/2 teaspoon at a time and testing the mix after each addition. The finished mix should feel like damp sand in your hands. It should not feel wet. If you think you have added too much liquid, add a little corn starch as needed. 

6. Now lets get ready to mold. Fill the mold you chose with some of the mix. Add as much as you need so the powder is compressed in the mold, it should be tight. You can leave it in the mold or remove it. I decided to remove it and it kept its form. Some people find that it is almost impossible for it to keep its form after it is removed. So if you've never done this before, leave it in the mold until it's completely dry. 

7. Let it dry for 24 hours. 

Step 3: Finished Product

 The bath bombs should feel hard and very dry on your hands when they're ready. The reason you see red bath bombs is because I'm showing you a different batch I made. Your finished product should look somewhat like this ones, depending on the color or shape you used. 

Keep them in a dry place for up to 6 months. You can add them to your bath with warm or cool water. 


To see more, you can go to my site. 

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38 Discussions


3 years ago

I think we add the wet ingredients to fast or we stir too much. Our bath bombs we very solid and in the molds but the oils is leaking out. Help

I am not really certain of this answer because I've never used cream of tartar but the citric acid (also called lemon salt) is what makes the baking soda fizz. Kind of like baking soda and vinegar

It varies depending on mold sizes and how much you pack into the mold. Really big ones compareable to Lush usually 2 1/2 but unless you have extra help dont make anymore than that at a time because it will get hard to work with and not stay together really well


Reply 5 years ago

I found citric acid in the canning isle at the grocery store.

 I buy Citric Acid in Soap Making specialty shops. I guess you could also find it in health stores. Or try ebay and etsy. 


6 years ago on Introduction

Made my 1st batch of bath bombs. They crumbled 5 times but I kept trying and finally got them to staying half mold. They did pop out, but they are showing cracks. What can I change next time image a batch? Also I tried to use the silicone ice trays and they crumbled each time. What can I do to use the trays next time.

1 reply

6 years ago on Introduction

instead of using corn starch, you can use white flour.


6 years ago on Introduction

I am going to make these for Christmas presents!


Reply 7 years ago on Introduction

OK! Just search up a few of the featured authors! A few personal faves of mine are: Soochmaroo,Kiteman,Belsey, and Jessyratfink. Hope you like it here!
courtesey of your local Maui The Gerbil!


7 years ago on Introduction

Hei, which oil can I use instead of coconut oil? or in what place can I buy it?