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Quals will be held online, 48 hours, tentatively starting at UTC 00:00 May 1st – might be April 30th for you!

Register here

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Keep an eye on our twitter account for updates.


Only the world’s top teams make it to DEF CON. This enables the event to explore the cutting edge of the amazing things that the world’s hackers are capable of. But the trick, of course, is figuring out who these hackers are. In CTF, this is done through cut-throat competition.

Every year, the DEF CON CTF organizers select a number of prominent events in the CTF community as prequalifiers. The winner of each of these is automatically invited by the Order of the Overflow to compete in DEF CON CTF, and OOO completes the roster by selecting teams through our own qualification round (date TBA) as well as last year’s DEF CON champion.

We select pre-qualifying events according to several considerations. We always look for quality events that present a variety of interesting challenges to their participants. We look for both prominent events with an established history and promising up-and-comers. And we have an additional metric: connecting the various global hacker communities. We want qualifiers not only to represent quality and innovation, but also to enable DEF CON to be a place where top hackers from the different worldwide hacker communities come together!

To that end, the Order of the Overflow has selected the following events as pre-qualifiers:

Additionally, teams will prequalify through the following DEF CON events:

From these events, we will identify the top hackers in the CTF community, invite them to DEF CON, and watch them battle it out at DEF CON 29. See you there!