Flagship & recurring hackathons
These return every year (dates change). For college-specific events, use platforms-and-calendars.md.
Open source & civic tech
| Event | URL | Notes |
|---|---|---|
| NASA International Space Apps Challenge | spaceappschallenge.org | Global, open-data / space themes |
| FOSSY (FOSSY conference hack day) | fossy.us | North American FOSS community |
| Open Source Summit events | events.linuxfoundation.org | Often co-located hackathons / workshops |
| Wikimedia Hackathon | wikimedia.org/wiki/Wikimedia_Hackathon | MediaWiki / Wikipedia tech |
| FOSDEM devrooms / fringe | fosdem.org | Brussels, February — fringe hacking |
Prestige student (US-heavy, often on MLH)
| Event | URL | Notes |
|---|---|---|
| HackMIT | hackmit.org | MIT, September |
| PennApps | pennapps.com | UPenn |
| TreeHacks | treehacks.com | Stanford |
| HackHarvard | hackharvard.io | Harvard |
| Cal Hacks | calhacks.io | Berkeley |
| HackGT | hack.gt | Georgia Tech |
| HackIllinois | hackillinois.org | UIUC |
| HackDavis | hackdavis.io | UC Davis, social good |
| LA Hacks | lahacks.com | UCLA area |
| Hack the North | hackthenorth.com | Canada |
| Hack the Valley | hackthevalley.io | Canada |
| HackUPC | hackupc.com | Barcelona |
Web3 / infra
| Event | URL |
|---|---|
| ETHGlobal series | ethglobal.com/events |
| ETHDenver | ethdenver.com |
High school
| Event | URL |
|---|---|
| JAMHacks (MLH) | Listed on MLH schedule |
| Hack Club events | hackclub.com |