Category Archives: Ciphers

You were given a coded message. Unfortunately, the bottom of the page became slightly damp, rendering several of the characters illegible (these are represented by asterisks in the text below). Your challenge is to recover the password in spite of … Continue reading →

This was, as suggested by the title, inspired by the Enigma machine used to encode run-of-the-mill messages during the Second World War (more high-security messages were encoded with the Lorenz cipher). The Enigma machine was relatively easy to operate, and … Continue reading →

After the last cipher, Joseph Myers has overtaken Sam Cappleman-Lynes into first place. Will it remain this way? Only time will tell… Good luck.

Cipher Tuesday has been massively successful at coinciding with special occasions. We’ve had Christmas and New Year ciphers, and now this one lands on Shrove Tuesday (on reflection, I realise that will trivially happen every year!). So, to commemorate a rather exciting … Continue reading →

Neither of the last two ciphers have been solved yet; hence, I’ve made this one slightly easier for you. Good luck. The password is entirely lowercase and contains no spaces.

The previous cipher seems to remain unsolved, even though it is indeed solvable. It was originally created by a hermit living in the Adirondack mountains, and was first deciphered by Dave Greene. He subsequently wrote a message in the cipher and passed it … Continue reading →

As rasterised images invariably lose quality, this particular cipher is in the form of a PDF document. Click on the link to Cipher XIII to open it.  

This week’s cipher is a (non-invertible!) matrix of knots, which you can view by clicking on the image below: When mathematicians originally classified knots, they made the mistake of believing that two knots (10_161 and 10_162 in the original table) were different … Continue reading →

This cipher again is separated into two parts, namely an audio file and the following ciphertext. ZKIGPWQ SLZSIIJ PBJRQKI TIMFTBE PEIVCNP CVHFEHA OAXINDB PTGDPUO PSJRBEP ZAAAAAA Unless you’re pitch perfect, you might also find this useful: I’ll leave you to work out … Continue reading →

Assuming that this has been timed correctly, it should appear after the first minute of the first day of the new year. To celebrate this, today’s cipher is simply a matrix of 2013 binary digits. I’ll include this in both a … Continue reading →