We ended round 2 of last year's cipherchallenge.org with 8100 users registered-delighted that we had 9300 this year! The 3rd practice round just launched heading into the half term break & we'll return with the 1st competition round on 5/11/26. Really hope you will join us!
Harry
Harry
@cipher-challenge.bsky.social
Join Harry at the National Cipher Challenge, which invites school-aged participants to put their code-breaking skills to the test every Autumn. Created by the School of Mathematical Sciences @UniSouthampton.
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You are smashing it with sign ups for this years cipherchallenge.org competition! Tomorrow at 3pm we launch the third practice challenge, then pause for the competition to start on Nov 5th. It's not too late to join the fun!
It's not too late to visit the home of the National Cipher Challenge. We have one more open day planned on 7th November, so if you would like to see where cipherchallenge.org started and maybe meet some of the team behind it then head over to bit.ly/3UupTxe.
We are amazed at the take up for round 1 of this year's cipherchallenge.org competition. We had 8720 signed up easily beating last years total of 7400 at this point. Highest participation was from Wilson’s School (Wallington). Will we beat 10K this year? That's up to you!
Nearly 7,000 competitors signed up for www.cipherchallenge.org and everything is set for the practice run starting in ten minutes. It is not too late to sign up - free to UK schools and colleges - and the competition proper runs throughout the Autumn term, starting on Nov 5th!
The clock ticks down to 3pm on Oct 8th and this year's cipherchallenge.org. Three months of fun and frustration for schools across the UK (and let's be honest, a few that sneak in from abroad too!). The first practice challenge starts tomorrow, and we can't wait to see you there!
Ssh don't tell*, but cipherchallenge.org has soft-launched for a week of bug hunting before we go live with the 25th National Cipher Challenge! Registration opens 24/09, competition starts 08/10, but if you want a sneak peak ... *Actually, please tell everyone!
We are looking forward to the launch of the official competition challenges at cipherchallenge.org at 3pm this afternoon. If you want to find out why the three Charles (Babbage, Dickens and Wheatstone) need to talk to the US president, there is only one way to find out!
Just like last year we broke the records for Challenge 2 entries with nearly 8100 of you signed up to take part. Practice Challenge 3 starts at 3pm today, so if you haven't signed up yet head over to cipherchallenge.org to get involved
The clock is ticking down to the 3pm start of Practice Challenge 2 at cipherchallenge.org! We had over 7000 registered for the first round and there is still time to register for the competition. Hope to see you there!
We couldn't be happier with the response to the first cipher challenge this year. Over 7400 signed up already and we're still on the 1st practice challenge! Head over to www.cipherchallenge.org/ to to get your students signed up in time for the 2nd practice challenge tomorrow.
Over 5000 already registered at www.cipherchallenge.org ready for the practice challenges to start tomorrow at 3pm. If you are aged 11-18 and want to learn codebreaking and show the world what you can do then head over and sign up!
The 24th National Cipher Challenge is now open for registrations and we have already had 1200 sign ups. The competition starts on October 9th, so there is time to register your teams and get them investigating codes and ciphers. Catch up on our news at www.cipherchallenge.org.
Day 1 and we have reached our first 500 registrations at www.cipherchallenge.org already! Will we beat last year's record 9,000? That is up to you!
Ready to register for the National Cipher Challenge? The site opens tomorrow. Did you know that as a teacher you can monitor the teams at your school? You will be able to read more about that at www.cipherchallenge.org/how-to-bulk-...
Just a few days now until the 2025 National Cipher Challenge opens for registration! If you know someone aged 11-18 who might like codes and ciphers (or who might not yet know that they do!) then get them to take a look at www.cipherchallenge.org on Thursday.
We are looking for additional content to add to our Community page. You can read last year's at 2024.cipherchallenge.org/boss-your-ci... If you took part and would like to feature on this year's site, then do get in touch either here or by email at cipher@soton.ac.uk. We would love to hear from you!
Posters for this years www.cipherchallenge.org should be arriving in schools this week. If you want to help promote the competition, why not post a picture of the poster on your boards?
Want something to read on these idle summer days? You could take a look at this short article by one of our cipher challenge competitors: mathsrant.com/2025/07/28/t... (Not that the Elves at CC HQ are idle. Far from it - too much to be done in prep for the new adventure. More soon!
We are well underway with the competition at www.cipherchallenge.org, though it is not too late to get involved if you fancy it. You'll be joining over 8500 other participants & there are still 6 challenges to break over the next few weeks. The next one goes live at 3pm today. Hope to see you there.
Over 8,000 signed up ready to take part in the competition at cipherchallenge.org this year! The first competition challenge runs until next Wednesday, so it is not too late to join in. Hope to see you there!
We have over 8,000 subscribers for the first time ever.They are all beavering away at cipherchallenge.org and putting a LOT of pressure on the marking system. If you get errors submitting, then it may be worth waiting. It won't affect your marks and will give the chips a chance to cool down!
Tantalisingly close to 8,000 users registered at www.cipherchallenge.org with just over 24 hours to go til we publish the final practice challenge. Competition challenges start on November 7th, so if you want to join the fun head over to cipherchallenge.org and sign up! Teams or individuals welcome.
Half way through Challenge 2 in this year's National Cipher Challenge and we already have over 7,800 participants. Will we break 8000? It's possible, the first 3 challenges are for practice and we usually get a bunch more signing up at the 4th round. Head over to www.cipherchallenge.org to see why!
Challenge 2 is live and we look forward to seeing what you make of it. These are still practice rounds, so we're trying to make them accessible to complete newbies. If you have more experience then avoid using the support we put in place at cipherchallenge.org and see how fast you can break it.
Challenge 1 is now complete and the leaderboard will be published at 11am this morning. If you can't wait to see how you did then log in at www.cipherchallenge.org and download your certificates for part A and part B to find out. And don't forget, Challenge 2 goes live at 3pm this afternoon
Last day to submit entries to Challenge 1 at www.cipherchallenge.org. If you don't make the deadline 11pm tonight the next practice round goes live tomorrow at 3pm. If you miss that there's still time to register & compete in the other rounds, with prizes based on your scores in rounds 4-10.
A couple of days left to tackle the first practice challenge at www.cipherchallenge.org, but even if you can't join us yet there is plenty of time to get ready for the main competition challenges starting on Nov 7th. All are welcome!
At the end of round 1 last year we had 5800 competitors signed up. Here we are on day two with over 6500 already taking part in the competition at cipherchallenge.org. If you want to see why, head over and take a look. There's still time to join in!
While the majority of the cipherchallenge.org competitors come from the UK we have a number from UK schools overseas and even some who take part "just for fun" from around the globe. We thought you might like to see where they are, so courtesy of Google Analytics, here is a map:
After reaching 444 teacher registrations earlier this week we're now at a total of 5555 registrations (competitors and teachers). Head over to cipherchallenge.org to break the symmetry or get us up to 6666! (as in the 4-digit number, not its factorial, that would be, to say the least, implausible.)
444 #teachers have signed up for the National Cipher Challenge at www.cipherchallenge.org, which has a pleasing symmetry, but we would love more of you to discover what the competition has to offer your #maths and #computing pupils. So do head over to see if it might appeal.
5,000 sign ups and climbing ... How many will we get before the competition start on Thursday? www.cipherchallenge.org
If you want to see how your students are getting on at www.cipherchallenge.org then you can register an account and give them your monitoring PIN to add them to your list. Read more about it at www.cipherchallenge.org/how-to-bulk-...
Just 2 days 3 hours and 15 minutes until we launch the first challenge at www.cipherchallenge.org so we hope you are all registered or about to do so. If you need something to keep you occupied until then, then take a look at our News page or the puzzles section of our Forum for some ideas!
Just to say that we are trying to be a bit more disciplined with News items at www.cipherchallenge.org this year. Aiming for about one a day, but always willing to consider extras, so if you come across something you think we should highlight, get in touch. You can mail us at cipher@soton.ac.uk.
Over 2000 competitors in over 1000 teams signed up so far for this year's National Cipher Challenge. If you haven't registered yet, head over to www.cipherchallenge.org to join in the fun. The first challenge will be published on October 10th, so you still have time to get ready, but don't be late.
Looks like the site has woken up! www.cipherchallenge.org is the new place to hang out (if you like breaking ciphers that is!)
Closing in on the first 100 teams to register at cipherchallenge.org this year. How many more on day one?