Holiday DIY Gifts: Geek Bath Bombs

Bath bombs have become very popular over the last couple of years, so of course there are DIY recipes for the crafty at heart. But, there is a shortage of bath bombs for the GEEKY at heart. This article explains the basic process of creating a bath bomb and how to make it geek-inspired … and all in time for the holiday gift-giving season.

What’s in a bath bomb?

There are plentiful sites with instructions and videos on how to make bath bombs, all with varying degrees of complexity and success. We used the directions and recipe from Popular Science as they seemed to be the simplest and most direct. They go into more detail on their page, so feel free to reference them as well! But, before we get into the how’s, let’s look at the what’s, and get your planning started on the right foot.


ingredients for bath bombs
Ingredients for your DIY bath bomb / Photo credit: Courtney Langdon

Your dry ingredients will be:

  • Baking Soda: 8 oz., i.e. 1 cup. Found in the baking aisle.
  • Cornstarch: 4 oz., i.e. ½ cup. Found in the baking aisle.
  • Epsom Salts: 4 oz., i.e. ½ cup. Found in the first aid / bath supply aisles.
  • Citric Acid: 4 oz., i.e. ½ cup. Found in the baking and / or cleaning aisles. Of the dry ingredients, this was the hardest to find; if you can’t find it in the store, try online (I bought mine on Amazon).
  • Biodegradable Glitter: Optional (Can be pricey, so use it only on the outer layer to make it go farther).

Your wet ingredients will be:

  • Water: 1 tbsp. Found in your tap. 😉
  • Coconut Oil: 2 ½ tbsp. Found in the baking aisle.
  • Essential Oil: Optional. 2 tsp. This is for your scent if you want it, but don’t make it overpowering like bad aftershave. A little goes a long way.
  • Color: Optional. See below.


color dyes
Different color dyes / Photo credit: Courtney Langdon

Your basic options for color will be food coloring (artificial or organic), soap additives / mica powder, or colored bath tablets.

  • Food coloring is cheap and everywhere, BUT some people report that high dosages can stain your skin and bathtubs. Most coloring products, food coloring included, will say that they aren’t safe to use on grout or older bathtubs and you should try it on a small surface first. If you do use food coloring, the recipe calls for 4 – 6 drops depending on how intense you want the color.
  • Soap additives / Mica powders have a large variety of colors and are far less likely to stain, BUT they can be expensive and hard to find (I bought mine on Amazon). The best way to stretch them out is to start with a little color and add it slowly until you get the exact shade you want, and that way you don’t waste any.
  • Bath tablets are already meant for the bathtub and can be found with kids’ bath stuff, BUT they are limited in the variety of colors available. However, they are my favorite because I bury them in the middle of the bath bomb for the “mystery bomb” described in the idea section later.


Molds / Photo credit: Courtney Langdon

You can buy metal bath bomb molds if you plan on reusing them to make several bath bombs, but you’ll also need to find a way to wrap the bath bombs up afterwards for moving. You can get shrink-wrap bags and a heat sealer online, which looks nice, or you can put them in a plastic bag or in plastic wrap, which gets the job done but doesn’t look as nice. Just make sure they’re contained in case they start to crumble in transport.

Another option is plastic ornament balls, no joke! These perform the same function as the metal bath bomb molds but are cheaper. You can either keep them and reuse them like the metal molds OR you can give them as part of the gift. The benefit to the latter is that they will hold the bath bomb together (so no additional bags or wrap necessary) and the recipient can reuse it themselves as a DIY ornament or other craft project.

Next, let’s take a look at approximate sizes and you’ll know what will work for you. The recipe used here filled three medium plastic ornament balls when loosely packed with a bath tablet and small toy. Obviously you can get more bath bombs if you use a smaller size, but just make sure your surprise fits, too. There are example surprises shown with each bath bomb in the image below so you can see how they might fit.

NOTE: Sizes vary greatly, so make sure you look at the product descriptions. For instance, one metal mold set found online listed the tiny size below as “small,” extra small as “medium,” and small as “large.” However, the sizes shown in the image above and listed below are from plastic ornaments, which tend to be larger than the metal molds.

  • Tiny (not shown): 1.77 in. or 5 cm.
  • Extra Small: 2.17 – 2.25  in. or 6 cm.
  • Small: 2.56 – 2.75  in. or 7 cm.
  • Medium: 3 in. or 8 cm.
  • Large: 4 in. or 10 cm.


This is my favorite part of making bath bombs: the surprises inside! This is also where you can start to get geeky. Here are a few ideas for what you can include, but the biggest tip is to keep it small.

surprise charms
Surprise charms for your bath bombs / Photo credit: Courtney Langdon
  • Charms are fun and unexpected because you can find a large variety of styles in small sizes. If you’re worried about the charm being damaged when it’s covered in bath bomb, don’t be. These are household ingredients. However, if it makes you feel better, you can put them in those tiny, plastic resealable bags that you get with extra buttons and / or jewelry (you can also buy them online in different sizes).
Figurines / Photo credit: Courtney Langdon
  • Figurines cost a bit more, but are also more collectible. The ones shown here are diecast metal figurines sold by Nano Metalfigs.
Jewelry / Photo credit: Courtney Langdon
  • Jewelry is always a winner but also pricier, so save these for your really good friends and family.
Toys / Photo credit: Courtney Langdon
  • Toys are a fan favorite for all ages, including game dice, smaller plastic figurines, etc.

How do you make a bath bomb?

Again, we used the directions and recipe from Popular Science, which has more detailed instructions than here. This will get you through the basic steps, though.

Step 1: Whisk together your dry ingredients in a large bowl.

DIY geek bath bomb step 1
Photo credit: Courtney Langdon

Step 2: Combine your liquid ingredients in a separate bowl or cup.

Photo credit: Courtney Langdon

Step 3: Slowly add the liquid mixture a few drops at a time to the dry mixture, whisking thoroughly the entire time to prevent the water from activating the citric acid. If you add the liquid too fast and it starts to fizz and / or smoke, stop adding the liquid mixture and whisk the dry mixture until it stops reacting. When you’ve added everything together, the result should look like wet sand.

step 3
Photo credit: Courtney Langdon

Step 4: Add the mixture to your mold on both sides, including the surprise in the middle.

step 4
Photo credit: Courtney Langdon

Step 5: Press the mold halves together and let dry until the next day. You’re done!

Photo credit: Courtney Langdon

How do you make it GEEKY?

Okay, Geek Gals, get your creative on with one of the following ideas or branch out on your own. TIP: You can use a Sharpie marker to add designs to the outside of your ball!

  • MYSTERY BOMB = White with a hidden color tablet + Unknown Surprise
  • Galaxy Bomb = Blue & Purple & Glitter + Star / Moon / UFO / Alien Charm
  • Superhero Bomb = Primary Color (Red or Yellow) + Superhero Figurine
  • Robot Bomb = Grey & Glitter + Robot Toy
  • Mad Scientist Bomb = Green + Science Charm
  • Unicorn Bomb = Pink & Purple & Glitter + Unicorn Figurine
  • Pokeball Bomb = Red & White + Pokemon Toy
  • Steven Universe Bomb = Red & Blue + Acrylic Gem
  • Super Mario Bomb = Yellow + Plastic Coin

What combo would you create? Please share!


Featured image credit: Courtney Langdon/Geek Gals

4 thoughts on “Holiday DIY Gifts: Geek Bath Bombs

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s