The International Obfuscated C Code Contest

Logo by winner Matt Zucker
The International Obfuscated C Code Contest

The source winners of the 27^th IOCCC have been released. Congratulations!

Right now, you cannot submit an entry because the IOCCC is not open. We do plan to hold IOCCC28 in 2021.

Please see the watch the IOCCC news below for information on the next IOCCC.

Goals of the Contest

Obfuscate: tr.v. -cated, -cating, -cates.
1. 1. To render obscure.
  2. To darken.
2. To confuse: his emotions obfuscated his judgment.
  [LLat. obfuscare, to darken : ob(intensive) + Lat. fuscare,
  to darken < fuscus, dark.] -obfuscation n. obfuscatory adj
The IOCCC:
- To write the most Obscure/Obfuscated C program within the rules.
- To show the importance of programming style, in an ironic way.
- To stress C compilers with unusual code.
- To illustrate some of the subtleties of the C language.
- To provide a safe forum for poor C code. :-)

IOCCC news

2021-01-04
- Email to IOCCC, via this email address:
  q.2021@ioccc.org
  with the following two words (separated by a space) somewhere in the subject of your email:
  IOCCC 2021
  works again. We apologize for the Email outage of the past few days.
2021-01-02
- A temporary side effect of our move to using GitHub, Email to/from *@ioccc.org has been disabled. We expect restore Email service in a few days. When we do, we will announce restoration of Email service here.
- We sure to use URLs of the form https://www.ioccc.org/* that include the www. when accessing the IOCCC web site.
2020-12-31
- Released the winners of the 27^th IOCCC.
- Moved the IOCCC source tree and web site to GitHub. To access IOCCC, use www.ioccc.org, as use of URLs with just ioccc.org without the www. is not supported.
2020-07-25
- The winners of the 27^th IOCCC have been announced. Congratulations!
2020-03-22
- Due to current world events, we are extending the 27^th IOCCC until 2020-May-15 06:26:49 UTC
- The submission tool will now be active until 2020-May-15 06:26:49 UTC
2019-10-13
- The source code for the winners of the 26^th IOCCC has been released.
- The 27^th IOCCC will be open from 2019-Dec-26 06:01:41 UTC (Boxing Day)
  to 2020-Mar-15 06:26:49 UTC (Ides of March).
- The submission tool will be available around 2020-Jan-15 15:15:15 UTC.
- Draft Rules, Guidelines and IOCCC size tool for the 27^th IOCCC are available.
2019-06-16
- Due to some delays, we now plan to publish source and annotations in early July 2019.
2019-05-11
- The winners of the 26^th IOCCC have been announced. Congratulations!

Older news has been archived, but is not currently available