🎬 Watch first: Penny and Dot explain Pigpen

Press play to meet Penny and Dot, the secret agent pigs.

TOP SECRET · SPY SCHOOL

The Secret of the Pig Pens

Almost 300 years ago, a secret society called the Freemasons used a clever code to keep their notes private. They didn't scramble letters. They drew little pictures. Soldiers in the American Civil War used it too!

It's called the Pigpen cipher because each letter lives inside a little "pen," like the fence around a pig. It's also called the tic-tac-toe cipher, since the pens come from tic-tac-toe boards and X's.

Your mission: learn the key, crack seven secret messages, and by the end, read Pigpen with almost no help at all.

A pig detective studying a secret message with a magnifying glass
A little pig sitting inside a stone pen
A pig in its pen. In Pigpen, every letter gets a pen too!

🔑 The Pigpen key (tap a letter!)

Two tic-tac-toe boards and two X's hold all 26 letters. The second board and the second X have a dot in each pen. Tap any letter to see how its symbol is made.

⚠️ Heads up: the letters in the X shapes are arranged differently on some charts you'll find online. That's normal, because Pigpen has many versions. Always use the key on THIS page for these codes.

✏️ How to make a symbol

1Find your letter in the key and look at its pen.
2Draw only the walls around that letter. Skip the walls that are open.
3In the dotted board or dotted X, add a dot inside.
4To DECODE, do the opposite: match the shape to its pen in the key.

🧪 Practice: write in Pigpen

Type a word and watch it turn into Pigpen symbols.

A pig writing a secret message with a feather pen by candlelight

🎯 Practice: name that symbol

How many in a row can you get? Reach 10 to earn the Key Master badge!

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