DEF CON 35 Las Vegas

How full will Vegas be during DEF CON 35?

Busy: expect firmer rates near the venue; book private dining and group blocks early.

DEF CON 35 falls mostly in the week of Aug 2, 2027, which we rate Busy: about 57,333 trade-show attendees in town (pro-rated), counting DEF CON 35 and 3 other tracked shows that overlap its dates.

1 show(s) in this window have no published attendance, so the real number is higher.

Overlapping shows

• Black Hat USA 2027 Jul 31 - Aug 5, 2027 · Mandalay Bay Convention Center · ~23,000
• Ai4 2027 Aug 2-5, 2027 · The Venetian · ~12,000
• ASD Market Week - August 2027 Aug 3-5, 2027 · LVCC · ~30,000

Each Monday-Sunday week gets one score: the pro-rated attendance of every tracked trade show in town that week. The score sets the week label. A show carries the label of the week that holds most of its days (ties go to the busier week), and on a week page every show card carries that week’s label, so a tile and its week never disagree. Method.

When to book entertainment for DEF CON 35

Book entertainment: Plenty of time

Based on typical lead times for headline and booth entertainment (status as of Oct 18). In Packed or Sold-out weeks, book at the early end; private rooms and hotel blocks go fast too.

Past editions

No past edition with a verified attendance figure on file yet.

Sources and notes

No official count is published. Community estimates for DC34 were ~24,500-26,000 (r/Defcon); not used. Cash-only badges, a casual crowd.

• Dates: https://defcon.org/
• Attendance: no verified figure, so this is left blank.
• Official site: https://defcon.org/

Spotted a change? Dates and venues are set by the organizer and can move. Always confirm on the official site.