What Are Bath Bombs: Learn How To Easily Make The Best Bath Bombs You’ve Ever Had!

by | DIY & Craft, Unwind

Disclosure: This post may contain affiliate links. If you use them to purchase items, then we may earn a small commission. Hope you find something that you like!

What Are Bath Bombs?

What are bath bombs? It’s hard to imagine many people never having at least heard of a bath bomb. However, knowing exactly what they are, and the ingredients may be a different story.

what are bath bombs

Do you really know what you’re putting in your bath water?

Have you ever actually looked at the ingredients, prior to placing it in your bath?

Within this post, we’re going to discuss just that. Additionally, we’ll discuss a simple, but amazing recipe, that will work every time.

The bottom line is, bath bombs are super fun, but there is a learning curve to getting them to live-up to your dreamy expectations. If you’ve ever made one, maybe you to, know the feeling.

Have no fear, we’ll guide you through!

The Bath Bomb?

Can you go into any beauty store and not find bath bombs? Oftentimes, trends lose their steam, and fizz away (no pun intended). However, it seems the market for bath bombs continues to grow.

Bath bombs are simple, spherical shaped balls, that dissolve, fizz, spin, or float once placed in water. What makes them extra special is the amazingly fresh and soothing aroma they disperse, simultaneously.

Fast forward to 2022, bath bombs have become more elaborate then ever! Most notably, they can be designed to look like almost any object, while still have that same fizzing, bubbly, and exploding characteristics.

Quick Chemistry Lesson:

Understanding the reason bath bombs do what they do is also important.

bath bomb chemistry lesson

Why do they fizz?

The basic fizz action is created by two ingredients. Firstly, baking soda. Secondly, citric acid. Basically, it’s a reaction between an alkaline substance in baking soda, and an acid (citric acid).

Lastly, water is introduced. When water is introduced it activates the reaction. Surely, other ingredients often play a role as well. For example, a binding agent like witch hazel can be used to help moisten the mixture and help adhesion.

Furthermore some ingredients slow the reaction down to achieve a longer fizz. We’ll get to specific ingredients in a moment.

What About The Aroma’s

Firstly, let’s discuss some of the aroma’s and colorants used, prior to getting to the staple ingredients.

20 years ago (and even today), you walk into Lush and what’s the first thing you notice. The aroma’s right? Oftentimes, this is your initial attraction to bath bombs, is the aroma explosion.

colorants found in bath bombs

Next, you notice the vibrant and vast palette of colors, while others pay close attention to what they are intended to do. 

So what makes up the aroma’s in a bath bomb?

Oftentimes, you’ll find the main components that make up the aroma’s are fragrance oils or essential oils. A combination of the two, can also be used.

With this being said you don’t need a scent to enjoy a bath bomb, if that’s your preference.

Keep in mind when scenting bath bombs with fragrance oils, understanding IFRA rates is also important. You see every fragrance oil has a limit to the amount of it you should safely use in your recipe.

If using essential oils, a good rule of thumb is 5 drops of oil per bath bomb made. This is usually a safe usage rate. Furthermore, essential oils can be very potent.

Keep in mind, some are not recommended during pregnancy, or with sensitive skin types.

A Word On Colorants:

colorant usage rate in bath bombs

We cover colorants extensively in another post, however there are generally a few types of colorants used in bath bombs.

  • Dye’s: Dye’s are pure pigment. Also, they are water soluble, meaning you don’t need an emulsifier. Bloom your dyes for most vibrant colors.
  • Lakes: Lakes are dyes combined with salts. They are not water soluble. Lakes crate bright colors. Add polysorbate 80 (emulsifier) to disperse these colorants in water.
  • Mica’s: Mica’s come in a vast array of colors. They are colored using dyes and other natural pigments. They are not water soluble.
  • Clay’s: Clay’s are natural. Also, they help to harden bath bombs and offer a subtle color. Be careful to stay light on usage, as they can leave colored residue on the tub.

When it comes to bath bombs colorants it’s all about experimentation. Furthermore, this is true when making bath bombs in general.

Don’t get down on yourself if your bath bomb fails the 1st, 2nd, even 10th time. As you practice, you will learn what works and what doesn’t.

Embeds & Other Additives:

Lush is a company you’ve most likely heard of. For us, they are the first company we saw placing additives or embeds within there bath bombs.

For example, their classic Sex Bomb. This now includes rice paper flower embeds.

There are lot’s of fun ingredients that can be added to bath bombs, usually to serve one or more purposes.

bath bomb additives

For instance, some additives make your skin feel soft. This includes certain oils, even milk-based bath bombs. Additives like oatmeal have been touted for soothing itchy skin.

Maybe you’ve witnessed a bath bomb that starts as one color and then disperses more as it dissolves in water. This is due to colored embeds being placed within the bath bomb when molding.

Today, bath bombs have become very detailed and intricate in both their ingredients and design. There are even bath bombs with surprises, like rings inside.

Ingredients Continued…

Surprisingly, to make a bath bomb it really only takes a few ingredients and a simple round mold.

Surely, companies include upwards of 10+ ingredients.

In the simplest of bath bombs the ingredients consist of baking soda, citric acid, colorant, and a scent. Often, you’ll find this mixture leads to a “fizzing bath bomb”.

baking soda in bath bombs

Other popular ingredients:

  • Cornstarch: Helps to regulate the rate of fizz. Cornstarch can also be added to help a bath bomb float.
  • Cream of Tartar: Some suggest it helps to bind or harden the mixture.
  • Kaolin Clay: Helps harden a bath bomb. Too much can leave your bath bomb sitting at the bottom of the tub, however.
  • Salts: Examples include Epson, sea salt and Himalayan salt. Salts have known minerals beneficial for your skin.
  • Carrier Oils: Examples include avocado oil, and sweet almond oils. Helps to sooth and hydrate the skin. Can also help to moisten your mixture to hold form. *Oils can also make the tub slippery*.
  • SLSA (sodium lauryl sulfoacetate): Adds lots of bubbles. Derived from coconut and palm oil.

Brambleberry does a nice job at explaining how to make a simple Lavender Relaxing bath bomb.

Are They Easy To Make?

Short answer, yes. But it depends on a lot of factors to get just right!

Bath bombs are extremely finicky. They are made up of common ingredients and certainly can be made by anyone in the comfort of your home.

easy to make bath bomb

However it’s also extremely easy for your bath bomb to go south. For instance, understanding the humidity/climate in which you live and how it can effect your mixture.

Many other questions have to be taken into consideration.

  • Is your bath bomb to wet/heavy and crumbling or not holding it’s shape?
  • Is your bath bomb to dry and falling apart in the mold?
  • Does it sink when you want it to float?
  • How do I make them spin?
  • What’s the process for storing a bath bomb?
  • How long will it last stored in the perfect environment?
  • How do I package them if I want to sell them?
  • Why did my homemade bath bomb develop raised bumps or warts after molding them?

You see, there is no way to make perfect bath bombs without first running into some of these problems (in our experience) and then correcting them one-by-one with each batch.

The idea is easy, however carrying out the idea is sometimes not so easy, so just keep that in mind and try not to get frustrated when first starting.

The Feel:

You’ll know when you feel it.

Above all, you will know when your mixture is right. Specifically, if the mixture is to wet, vs. to dry. It’s oftentimes, all in the feel.

Even if you have to tweak a recipe because of the environment, your feel can be a good indication of whether the altered recipe will succeed.

Tips For Beginner Makers:

tips for beginner bath bomb makers

Tip 1: Measure Everything:

One of the most important criteria’s to making bath bombs is to measure. Know what works and what doesn’t work from batch to batch.

Furthermore, use measuring cups, spoons. Ideally use a scale (in grams) to know exactly how much of an ingredient you have used. This allows you to duplicate your results or tweak the recipe.

Tip 2: Molds

Use rounded molds with little detail to start. Although you may have scene a really cool mold, practice with simpler designs first. Once you have a knack for the process, experiment with more detailed deigns.

Tip 3: One Color

Experiment first with one color. For example, make one batch of blue bath bombs. Afterwards, if they come out the way you like, try adding a second color. Third, and so on.

Tip 4: The Environmental Effect

It’s true. The environment plays a huge role when making bath bombs. Your formula or recipe will almost always fluctuate if the climate is humid vs. dry. Rainy vs. sunny.

how climate can effect bath bombs

The air effects moisture levels and can be a reason your bath bomb “fails”. Furthermore, you can resist these issues, somewhat, with a dehumidifier. Oftentimes, keeping the humidity below 45 equals success, in our opinion.

We discuss this more in our troubleshooting bath bombs article.

Tip 5: Hardeners & Clay’s

Clay has a few benefits within the realm of bath bombs. Firstly they add a lovely skin softening characteristic. Secondly, they help to harden your bath bomb.

However, don’t be fooled into using to much clay, as it can cause your bath bomb recipe to become to dry and heavy. If you’re looking for a spinning and floating bath bomb, you’ll want to be mindful of this.

How To Make The Best Bath Bomb for Beginners:

(Ingredients, Ratio’s & Steps)

Dry Ingredients:

  • 1000 grams sodium bicarbonate
  • 500 grams citric acid
  • 1 TBS SLSA (sodium lauryl sulfoacetate)
  • 1/4 TBS kaolin clay
  • 1 TBS cream of tartar
  • 1/2 TBS corn starch

Wet Ingredients:

  • 1 TBS sweet almond oil
  • 1/2 TBS avocado oil
  • 1/2 TBS polysorbate 80
  • Witch Hazel: 3-5 sprays
  • Essential oil 5 drips per bath bomb (dependent on mold size)
  • Coloring of Choice: Water soluble dye. 1/8 tsp dye : 1 tsp water (place just a few drops into mix to desired colored)


Step 1: Blooming Dyes

The very first thing we do if using dyes, is bloom them. That simply means adding the dye to water to help bring out their vibrant color.

Step 2: Add Dry Ingredients (-) Citric Acid

Measure and combine dry ingredients in a large bowl. This includes you baking soda, cornstarch, SLSA, cream of tartar, and kaolin clay. Furthermore ,when adding the dry ingredients, it helps to run them through a sifter.

If you use milk powder, arrowroot or nearly any other dry ingredients, you would also add them here.

Step 3: Add Wet Ingredients

Next, measure and combine you wet ingredients. This includes your fragrance, bloomed dye(s), oils, and polysorbate 80 (emulsifier).

Then add this to your dry mixture, continuing to mix as there’re added. After those are mixed I assess the mixture because at this time, the mixture should not be completed.

The easiest way to mix (for us) is a stand mixer. It’s hard to over mix this recipe. Turn on your mixer and let it go for 3-5 minutes. This will really help the dye become dispersed evenly in the mixture.

Step 4: Add Citric Acid

Now that you have this beautiful mixture well incorporated, add citric acid.

Why now?

Remember the short chemistry lesson from earlier? If you add sodium bicarb early, as well as your wet ingredients (like the bloomed dyes in water), it risks starting a chemical reaction, prematurely.

Adding citric acid at this stage, makes sure this will not occur.

Step 5: Witch Hazel

Grab your spray bottle of witch hazel, because we’re not quite done. At this stage there are different schools of thought. Some people use alcohol in damper climates, because it evaporates quickly.

Are there alternatives?

Yes, some makers use distilled water in dry climates. Oftentimes, with alcohol, you’ll be spraying your mixture over and over, because it does evaporate that quickly.

For us, it limits our time with the mixture being “just right”, for molding.

Water can cause the chemical reaction to occur, like we discussed prior. Also, too much, can easily lead to a very wet and expanding mixture.

It’s all about experimentation. However, if you can keep your humidity level under around 45-50%, witch hazel works great. With a few sprays it moistens your mixture and stays moist, long enough to mold.

The idea here is to spray x3. Mix your ingredients. Get a feel for consistency. If a little dry, add a few more sprays.

At this time, we prefer to hand mix. This helps us feel the mixture better, which we’ll discuss more in a second.

This is all there is to it, with this particular recipe. However, when do you know it’s ready to be molded?

When Is My Mixture Ready For The Mold?

There’s becoming a more well known basic “test” to tell if a mixture is ready to be molded.

The squeeze and drop test!

Simply squeeze your mixture, then drop it from about 6 inches above your mixing bowl. Afterwards, if the mixture stays together and does not stick to your gloves, it’s usually ready to go.

However, if your mixture crumbles, generally it needs more moisture.

Keep in mind this is a basic mixture. Oftentimes, there are other additives you can use, but will require you to be more well versed in the process.

Then, add this mixture to your round mold. Overfill both sides of the mold and then press together. The sides may not touch and that’s okay.

The goal is compact the mixture. You can also try using a bath bomb press machine.

If you have the right consistency, the mixture only needs but a few seconds in the mold. Sit the bath bomb on something soft like foam egg carton material.

Consequently, a hard surface may cause the bottom to flatten.

How To Dry Your Bath Bomb:

The drying process is crucial. Place them in an area preferably with low humidity. Humid conditions may cause moisture retention.

After setting them aside, as tempting as it may be, let them dry!

Allow the witch hazel and water to evaporate. If you chose to use clay or another hardener, they may be dry enough to handle within 24 hours.

Final Thoughts!

Follow these steps and you are well on your way to making the best bath bombs you’ve ever made.

Bath bombs are easy to make, but hard to perfect and get just right. If you enjoyed the post, be sure to share on your social media platforms for others to read.

From here at RN To Zen, thanks for stopping by!


Disclosure: This post may contain affiliate links. If you use them to purchase items, then we may earn a small commission. Hope you find something that you like!
manduka yoga gear
prana yoga gear
nurture soap products

Don't Miss Out

Get updates, top yoga recommendations, and an exclusive preview of our upcoming products!

Success! You subscribed to the RNtoZen newsletter