ONHBNational Olympiad in Brazilian History
Phase 1 · May 4–9, 2026
2026–2030 calendar
Competition calendar
Tech competitions highlighted (⚡), science olympiads, hackathons and more. Filter by age and click an event for details.
⚡ Upcoming tech dates
48h HackathonsMLH GHWOnline hackathon weekNov 6–12, 2026happening now</> ProgrammingBebrasWorld-Wide Bebras Week of computational thinkingNov 9–13, 2026happening now🔐 CybersecurityCSAWCSAW Cybersecurity Games Global FinalsNov 12–14, 2026in 2 days48h HackathonsJunctionHackathon (48 h)Nov 13–15, 2026in 3 days
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Long registration periods appear only on the days they open and close.
This month's competitions
May 2026
4 dates
ONHBNational Olympiad in Brazilian History
Phase 2 · May 11–16, 2026
ONHBNational Olympiad in Brazilian History
Phase 3 · May 18–23, 2026
ONHBNational Olympiad in Brazilian History
Phase 4 · May 25–30, 2026
Confirmed: official days · Month announced: days to be confirmed · Estimate: the month it is usually held, not announced yet · No forecast: date unknown.
Dates checked on the organizers' official websites and calendars (last review on November 6, 2026). They may change: always confirm on the official website before registering or traveling.