Only One Enigma Code Has Never Been Broken

Enigma was cracked in World War II, but one message was never solved.


Jack Dunhill


Jack Dunhill

Social Media Coordinator and Staff Writer

Jack is a Social Media Coordinator and Staff Writer for IFLScience, with a degree in Medical Genetics specializing in Immunology.

Social Media Coordinator and Staff Writer


The Enigma machine was a groundbreaking piece of engineering. 

Image credit: Wirestock Creators/

Through genius and brutal hard work, an international effort led by British code-breakers cracked the infamous Enigma code. Any communications that weren’t understood during the war were subsequently deciphered by scholars and internet users, except one. A single German Navy message has withstood all attempts to break it and, to this day, no one knows what is written inside. 

The Enigma code

During World War II, the Axis forces communicated through a groundbreaking encryption mechanism called the Enigma machine. Using a series of rotating dials that would be set in a specific position at the start of each day, the dials would turn an inputted message into an almost indecipherable code before it was sent to the receiving party, whose Enigma machine (programmed to the same daily position) would then decipher it. Only an Enigma machine programmed to the correct position would be able to reveal the message, allowing the Germans to send messages with impunity.  


The beginning of the war saw countless attacks coordinated by messages that the Allies were perfectly capable of intercepting, but unable to ever read. Even if they captured an Enigma machine, by daybreak the next morning, it was almost useless. 

Prior to World War II, though, a bright group of Polish mathematicians were hard at work trying to crack Enigma. They got their hands on a manual and began understanding how the delicate machine worked, allowing them to create replicas (named “bombes”) that could speed up the decryption process. They were the first to officially decipher an Enigma cypher and had a very good success rate, until the Germans introduced more rotors into the machine, vastly increasing its complexity. 

At the beginning of the war, Poland handed their extensive work over to the British, who set about creating a taskforce. The top-secret (and now world-famous) team at Bletchley Park, which included Alan Turing, used a team of incredible mathematicians to try and manually decode the cyphers, a process that was arduous and almost always a failure. 

One brainwave did have a huge effect, though – they discovered that the messages almost always contained “Heil Hitler” at the end. Through this, the team were able to get a kickstart on deciphering the messages each day. 


Through the collective of some of the brightest minds in Britain, the original data from the Polish mathematicians, and guidance from the father of computing himself, the team created one of the first-ever computers, designed solely to decipher Enigma messages. The British Bombe cycled through a huge number of combinations, with the “Heil Hitler” shortcut programmed in, and was finally able to crack the code in a timely manner. 

British bombe
The British Bombe used a large number of rotors to cycle through possible combinations.
Image credit: Rob Atherton/

However, it couldn’t do them all. Some messages – often shorter ones – were unbroken during the war, leaving a tantalizing puzzle for internet users who are fans of encryptions. Modern computers can process Enigma messages at a blistering speed, and as code-breaking has advanced many haven’t survived the combined power of the internet. All except one. 

The last remaining Enigma message

P1030680 is a German Navy message from 1945 that has never been deciphered. Standard methods for deciphering Enigma messages have resulted in pure gibberish when used on this note and there is almost no information to get a head-start on it. Instead, the online code-breakers have resorted to recruiting raw computing power to try and brute force the message down, but it still remains a mystery to this day.  

What makes this note so difficult is that it is quite a small message and that the initial Grund tables (the initial settings) are no longer available, so there is very little to go on when beginning to decode the message. The Enigma@Home project has been trying since 2018 to break this single code and it hasn't worked out so far.


Give it a go yourself here – maybe you could break the last Enigma message. 


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  • World War 2,

  • Nazi Germany,

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  • codes