Introduction: How to Make Color Changing Slime

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If you find yourself bored with regular slime recipes, color changing slime is a great new way to play! This slime is made using thermochromic pigment, allowing it to change color based on the temperature of the slime.

Thermochromic pigments are available in a wide variety of colors and temperature ranges, so you can change the color of the slime using cold or hot temperatures.

I especially like color changing slime because you can shift the colors over and over again - it never gets old watching the slime change instantly to a new color and fade back to its original color. :D

Step 1: Ingredients + Tools


Double check that the saline contact solution you're using has boric acid as an ingredient, otherwise the recipe will not work.


  • Bowl for mixing
  • Measuring spoons
  • Spoon for mixing
  • Small air-tight container for storing (optional)

Step 2: Combine the Glue and Baking Soda

Pour the glue into a bowl and add 1 tablespoon of baking soda. Stir it together until the mix is homogenous - you don't want to see any dry spots or clumps of baking soda!

Step 3: Add the Thermochromic Pigment

Now you'll want to add in 1/2 teaspoon of the thermochromic pigment. Stir the mix until you see no dry spots left - you'll probably need to scrape down the sides of the bowl to get all the pigment properly distributed in the glue.

Step 4: Add in the Contact Solution

Now you'll want to add in the contact solution one teaspoon at a time.

Add the first teaspoon and stir well. Then, add the second teaspoon and begin to stir. The slime mix will begin to clump together around the spoon and pull away from the sides of the bowl.

Step 5: Kneading the Slime

Remove the slime from the bowl - don't worry if it's super sticky. We'll fix that by kneading!

Knead the slime between your hands for a couple minutes until the stickiness fades and it becomes more solid. At this point, you can use the slime blob to clean any stray slime on your hands or in the bowl.

Step 6: Time for Color Changing!

Once your slime is done, you can change its colors in a variety of ways. Depending on the thermochromic pigment you chose, you'll need to either cool down (ice cubes) or heat up (body heat, hair dryer, warm/hot water) the slime.

In my case, the pigment changes from purple to teal at 92 F so I used hot water!

The best part about color changing slime is that you can heat it up and cool it down over and over - it's really fun to stretch and play with the slime until it returns to its normal color. :)

(The one caveat here: if you do use hot or warm water, don't worry about "drying" the slime off when you remove it from the water. The water won't cause any problems, but trying to dry it will. I ruined my first batch by fusing it accidentally to a paper towel. Whoops!)

Enjoy your slime and post pictures if you make it! :D