We are awfully sorry to inform you that due to technical difficulties Finals of 15th Challenge24 has to be postponed between 26th and 28th of June.

Thank you for your understanding!


Winners of 2013

Register here!

Get ready for the EXTREME challenge!

Challenge24, The International 24-hour Programming Contest, is one of the few contests where participants are free to choose their tools, platforms and programming languages, and problems are presented only using open file formats.

Challenge24 is held every year in Budapest on the last weekend of April or the first weekend of May.

Electronic Contest (EC) is a five online qualification round.



Electronic Contest

Congratulations to the team HoChockiGon!


Electronic Contest

28th February 10:00-15:00 (CET)

Problem set: please download the encrypted problem set from one of the mirrors listed here!

Passwords to the zip will be published exactly at 10:00 CET (first on IRC).

Outer password: Eegaema1Eo6a

Inner password: HeiPh8ohv5ph

Input 7-10 for task F


Preliminary Electronic Contest results

Congratulations to the team epiphallar_caecum!


Preliminary Electronic Contest

21st February, 10:00-20:00 CET

Problem set


Challenge24 and Deadline24

Get ready for TWO EXTREME challenges!

Have you got enough time? The 7th Deadline24 is waiting for you, a day after our Challenge24 Electronic Contest.

Application deadline: 26th February, 2015 (as Challenge24 ;-) ).


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Do you like Challenge24? Help us, share this video with your social network!


Are you ready? Register now with your team!

You can register now here

Share the Challenge24 spirit!


Jubilee competition is coming!

The registration is coming soon, but the important dates are ready

We kindly recommend to you to watch this video:

MPG (Download)

Jubilee Challenge 24 in 2015

We're now announcing the dates of contest days in 2015!

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