Creating your own DIY invisible ink is a fun activity for many ages. Plus, you probably already have everything you need for at least one of these five ways to do invisible ink.
It’s fun to make secret messages! Using invisible ink might be a fun thing to incorporate into a spy game or a scavenger hunt.
This project also serves as an enjoyable at-home science experiment as kids can observe the reaction between acid and heat to create many of these invisible inks.
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Invisible Ink – White Crayon
Using a white crayon to draw pictures or write secret messages on a white piece of paper is the easiest invisible ink technique. This is safe for all ages. You reveal the message by painting over the crayon with watercolor.
Invisible Ink – Baking Soda
Stir together equal parts baking soda and water (like one tablespoon + one tablespoon). Then, use a Q-tip to write a message on blank, white paper with this mixture. Allow it to fully dry, then reveal the message with water color.
The baking soda invisible ink method is safe for all ages as well.
Invisible Ink – Lemon Juice
Add a drop or two of water to the juice from half a lemon. Then, use a Q-tip to write a secret message on a blank, white piece of paper. Allow to fully dry.
To reveal the message, carefully hold the paper above a candle, letting the heat reveal the message.
The lemon juice invisible ink technique is best for older children and must be supervised as using heat (from a candle or another source) could be dangerous for younger children. Use your best judgment.
Invisible Ink – Vinegar
Add a tablespoon or two of vinegar to a small bowl or glass. Then, use a Q-tip to write a secret message on a blank, white paper. Allow to fully dry.
To reveal the message, carefully hold the paper above a candle, letting the heat reveal the message.
The vinegar invisible ink technique is best for older children and must be supervised as using heat (from a candle or another source) could be dangerous for younger children. Use your best judgment.
Invisible Ink – Milk
Add a tablespoon or two of milk to a small bowl or glass. Then, use a Q-tip to write a secret message on a blank, white paper. Allow to fully dry.
To reveal the message, carefully hold the paper above a candle, letting the heat reveal the message.
The milk invisible ink technique is best for older children and must be supervised as using heat (from a candle or another source) could be dangerous for younger children. Use your best judgment.
Above, you can see (from top to bottom) the results from: lemon juice, milk, and vinegar invisible ink.
If you use any of these invisible ink techniques, let us know what you think and what worked best! Happy spying 🙂
More Science Experiments to Try:
I love that there are multiple methods we can try for making our invisible ink. Such a fun project!