We’ll carefully review each submission, giving the C code and remarks.md
the time and attention they deserve.
Winners will be announced live on the "Our Favorite Universe".
https://www.youtube.com/@OurFavoriteUniverse
PLEASE subscribe to that YouTube channel and click the notification bell.
The winning source will be uploaded to www.ioccc.org at the end of the show.
We may also post progress updates on Mastodon:
And Discord server. To join:
The IOCCC is now closed for new submissions.
For the many who submitted to this IOCCC, we THANK YOU. Without your
efforts, talent, creativity, and C coding skill, there wouldn't be an IOCCC!
If you missed this IOCCC, please submit to the next IOCCC, which we
are happy to announce we are planning to hold another IOCCC next year.
The IOCCC judges will go into "radio silence" as we judge the many
submissions. How long depends on the submission quantity & quality.
The 29th International Obfuscated C Contest closes at 2026-03-13 17:19:23.293137 UTC.
You have less than a week to upload your submissions to the International Obfuscated C Code Contest!
For details see this free Patreon post:
The IOCCC29 is open for less than a month (2026-03-13 17:19:23.293137 UTC).
How register: https://www.ioccc.org/next/register.html
On receipt of IOCCC email, login and change your initial password: https://www.ioccc.org/next/pw-change.html
Re-register if you didn't change your initial password in 14 days.
Obtain the mkiocccentry toolkit: https://www.ioccc.org/faq.html#obtaining_mkiocccentry
Use the mkiocccentry to form your submission compressed tarball: https://www.ioccc.org/faq.html#using_mkiocccentry
Upload your submission: https://www.ioccc.org/next/submit.html
Happy 2026!
IOCCC29 is open for registrations. After you have registered, you have 14 days to then log in to the submit server and change your password. If you fail to log in within 14 days, your submit server will expire and you will need to re-register.
See: https://www.ioccc.org/quick-start.html#enter
For those who have registered, you may upload your submissions. Be sure you are using your latest version of the mkiocccentry toolkit:
The International Obfuscated C Code Contest (IOCCC29) is in "pending state," meaning the contest is open for you to register:
https://www.ioccc.org/next/register.html
Feel free to register today, even if you are not sure if you want to enter, instead of waiting until the last minute near the contest deadline.
On 2025 December 14th at 23:00 UTC, there will be an IOCCC Discord hangout to discuss IOCCC29. To join the IOCCC Discord server:
We have published a video on the IOCCC Patreon talking about the IOCCC29 contest as well as some of the more important changes to the rules and guidelines:
The IOCCC29 will run from 2025-12-03 20:25:12.045045 UTC to 2026-03-13 17:19:23.293137 UTC.
This contest will enter the pending state on 2025-12-03 20:25:12.045045 UTC, allowing people to register for the IOCCC:
https://www.ioccc.org/next/register.html
Rules & Guideline feedback welcome:
https://www.ioccc.org/faq.html#feedback
This contest will enter the open state on 2025-12-15 18:21:24.273033 UTC, allowing people to upload submissions.
For how to enter the IOCCC:
IOCCC