HOME     Making Pictures   Charts   Stationery   Family   Garden   Stories   Computer   Games   All

Write Messages in Code

Games List

Read Secret Messages Coded with Offset Letters*

To encode a message, follow these steps.

Type your message into the box.

In the slot marked "Key Value", type a number between "1" and "25".

Now click the button marked "Encode Message".

Highlight all of the encoded text, press Ctrl C, paste into Notepad and print.

Key Value:

To decode a message you’ve received, type it into the box. If you haven’t been given the "Key", type a number between "1" and "25" into the "Key Value" slot and click "Decode Message".


It's not very likely that your first number will be the right one, so be patient and methodical. Before you change the number or try the next, be sure to click "Encode Message" again to restore the original code.

Do this each time until you see intelligible words.
Then, with your left mouse button held down, drag across all the text to highlight it, press Ctrl C, paste into Notepad and print.

Scroll down for more about writing and solving codes.

Noughts and Crosses   Book Codes

*Offset Letter Codes

A letter offset code is very straightforward. Imagine that you have the alphabet printed out twice, as two lines on a long strip of paper.

If you cut the two apart and push the bottom piece of paper a little to the left, the A on the top line will be directly above the B on the second line.

Now suppose that you write the letter from the bottom line each time you mean a letter on the top line. "Pokemon" would become "Qplfnpo", which looks like gibberish, and only means something to the person who wrote it and those who are in on the secret. That is an Offset Letter Code with Key Value 1.

Obviously, there are 25 different Offset Letter Codes. Even though they are simple they can be very puzzling indeed. Without a decoding program such as this one, the code solver must use some ingenuity. Always look for single letter words. There are only two in every-day English, "I" and "a". Look for three letter words that are used often. They are quite likely to be "the" or "and". Also notice which letters are used most frequently. The letter "e" occurs more often in English than any other letter, and more words begin with "s" than with any other. All words must have vowels—but remember that "y" can be a vowel too. It may take some time, but you can always crack an offset code if you stick at it.


Noughts and Crosses

One very easy way to make up a code is to draw three copies of the grid that we use to play "Noughts and Crosses" or "Tic Tac Toe". Leave the first grid blank, put circles or dots into the second, and put crosses into the third. Write the letters of the alphabet at random in the three grids.

illustration of grids

You can then write words by drawing the shapes that are associated with the individual letters, like this:

"trampoline" encoded

You can make variations of this idea. Instead of putting symbols in the grids, you could draw one grid with single lines, one with double lines, and one with wavy lines.


Book Codes

Book codes are much harder to crack, because there is no logical order in the encoded material. Each person—the one sending the message and the one reading it—has a copy of the same book. What book it is doesn't matter at all, but the two copies must be identical. There would be no point in just agreeing to use "Alice in Wonderland", for instance, because that book has been printed many times and, although the words may be the same each time, they will almost certainly occur on different pages. The books have to be absolutely identical.

The message is written as a series of long numbers. The encoder turns to a page anywhere in the book and finds the letter that's needed. It might be "a". The person finds the word "darkness", which happens to be the seventh word on the fifteenth line on page two hundred and forty-one. The code for "a" will then be 2411572, made up of page 241, line 15, word 7, letter 2. The next time an "a" is needed a different page and word will be used, so that no-one can see a pattern in the coded text.

This sort of code must be rather boring to write and frustrating to decode. Nevertheless, skilled cryptographers can work out messages written even in this complicated way.


Free JavaScripts provided
by The JavaScript Source