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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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!

cipherchallenge.orgNational Cipher ChallengeAn annual codebreaking competition for UK schools and homeschooled students run by the School of Mathematical Sciences at the University of Southampton

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!

cipherchallenge.orgNational Cipher ChallengeAn annual codebreaking competition for UK schools and homeschooled students run by the School of Mathematical Sciences at the University of Southampton

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!

cipherchallenge.orgNational Cipher ChallengeAn annual codebreaking competition for UK schools and homeschooled students run by the School of Mathematical Sciences at the University of Southampton

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!

cipherchallenge.orgNational Cipher ChallengeAn annual codebreaking competition for UK schools and homeschooled students run by the School of Mathematical Sciences at the University of Southampton

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!

Thinking of all our Cipher Challenge alumni getting their results today, and the teachers and family who support them. Congratulations to all of you on getting to this point and wishing you all the very best in the next stage of your adventure wherever it leads!

Quick request for all the teachers out there who love the National Cipher Challenge. We will hold our 25th prizegiving at Bletchley Park in early 2027. Which of the following dates is best? 10th February (before half term) or 4th March (after half term).

We've a few tickets spare for the National Cipher Challenge event at Bletchley on 4th March. With speakers including Rob Eastaway. If you or your school took part in the competition in the Autumn, email us at cipher@soton.ac.uk with your details so we can see if we can fit you in.

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!

cipherchallenge.orgNational Cipher ChallengeAn annual codebreaking competition for UK schools and homeschooled students run by the School of Mathematical Sciences at the University of Southampton

Holding a Clubs/Societies/Enrichment Fair for your school or college? The National Cipher Challenge might be just what you need. Here is a poster you can use to promote it! The site will open for registration on Sept 18th and the competition starts Oct 9th. Challenges weekly throughout term!

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!

mathsrant.comThe National Cipher Challenge – More Than Just CodebreakingI’ve been meaning to write about how I got into codebreaking — so here’s the start of a small series on maths, ciphers, and curiosity. A lot of experiences have shaped the curious, questioning pers…

Just a heads up that now the challenge is finished we are working on the leaderboards, prizes and invitations to the National Cipher Challenge event @bletchleypark. Please do keep an eye out for messages from us on the site, and log in regularly to see if we have left one for you in your account!

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.

cipherchallenge.orgNational Cipher ChallengeAn annual codebreaking competition for UK schools and homeschooled students run by the School of Mathematical Sciences at the University of Southampton

PS, we are keen to hear about your experiences with the challenge, so do reply if you are happy to talk about it. And if you have any news that you would like us to share then reply or email us at cipher@soton.ac.uk to let us know.

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!

cipherchallenge.orgNational Cipher ChallengeAn annual codebreaking competition for UK schools and homeschooled students run by the School of Mathematical Sciences at the University of Southampton

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.

cipherchallenge.orgNational Cipher ChallengeAn annual codebreaking competition for UK schools and homeschooled students run by the School of Mathematical Sciences at the University of Southampton

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!

cipherchallenge.orgNational Cipher ChallengeAn annual codebreaking competition for UK schools and homeschooled students run by the School of Mathematical Sciences at the University of Southampton

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.

cipherchallenge.orgNational Cipher ChallengeAn annual codebreaking competition for UK schools and homeschooled students run by the School of Mathematical Sciences at the University of Southampton

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

cipherchallenge.orgNational Cipher ChallengeAn annual codebreaking competition for UK schools and homeschooled students run by the School of Mathematical Sciences at the University of Southampton

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.

cipherchallenge.orgNational Cipher ChallengeAn annual codebreaking competition for UK schools and homeschooled students run by the School of Mathematical Sciences at the University of Southampton

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.)

cipherchallenge.orgNational Cipher ChallengeAn annual codebreaking competition for UK schools and homeschooled students run by the School of Mathematical Sciences at the University of Southampton

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.

cipherchallenge.orgNational Cipher ChallengeAn annual codebreaking competition for UK schools and homeschooled students run by the School of Mathematical Sciences at the University of Southampton

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!

cipherchallenge.orgNational Cipher ChallengeAn annual codebreaking competition for UK schools and homeschooled students run by the School of Mathematical Sciences at the University of Southampton

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.

cipherchallenge.orgNational Cipher ChallengeAn annual codebreaking competition for UK schools and homeschooled students run by the School of Mathematical Sciences at the University of Southampton