## Playfair cipher: Is it breakable, if the message has only 40 letters?

My readers have shown that a Playfair cryptogram consisting of only 50 letters can be broken. Here’s a Playfair challenge with only 40 letters. Can you break it, too?

## “Famous uncracked codes” video on YouTube receives over a million hits

I have an appearance in a YouTube video that introduces the ten most notable unsolved cryptograms. More than a million people have already watched it.

## Cryptograms from the youth of a Canadian artist

Canadian artist Zen Rankin has published two encrypted messages he created in his youth days. Can a reader break them?

## A new solution approach to the Somerton Man cryptogram – does it make sense?

An alleged cryptanalyst has published a new hypothesis about the Somerton Man cryptogram on Wikipedia. Does it make sense?

## Unsolved: A numbers station code in a music video

A video by US musician Laurie Anderson contains a spoken sequence of numbers. Can a reader make sense of it?

## A postcard from 1909, encrypted in a strange number code

At first sight, an encrypted postcard from 1909 looks like many others I have introduced on this blog. However, the encryption method used is unusual.

## An unsolved encrypted telegram from the early 20th century

An encrypted telegram from Italy is unsolved. Can a reader find the codebook that was used? Without the codebook, deciphering the telegram is as good as impossible.

## Encrypted Thanksgiving greetings from the NSA

Two days ago, on Thanksgiving, the NSA sent encrypted greetings to “every NSA employee across the globe”. Can you break this encryption?

## A postcard with an abbreviated message

In 1913, an unknown person sent an encoded postcard to a man living in the then German town of Nieder-Jeutz. It is not possible to decipher this card unambiguously, but a few guesses can be made.

## Can you solve this strange cryptogram?

Once again, an unsolved cryptogram has been published on Reddit. No details are provided. It is not even clear what is above and what below. Can a reader solve this mystery?