NACLO 2026 - North American Computational Linguistics Open competition
Columbia University, Computer Science Department

Important Dates:

January 29, 2026
(Thursday)
10:00am-1:00pm (arrive by 9:30am)
Location: 414 CEPSR
NACLO Open Round (first round)

March 19, 2026
(Thursday)
Time TBA
Location TBA
NACLO Invitational Round (second round)

What is NACLO?

NACLO (the North American Computational Linguistics Open competition) is a contest in which high-school students, as well as middle-school students, solve problems relating to linguistics and computational linguistics. No prior knowledge of linguistics or second languages is required. Students may participate at their high school or at a nearby university site. This year, Columbia University will be one of the local university site for the New York metropolitan area. The open round of the contest will take place on Thursday, January 29, 2026. Well-performing students will be invited to the second (invitational) round, which will take place on Thursday, March 19, 2026. The top students in the second round will have a chance to participate in the International Linguistics Olympiad, one of thirteen international high school science Olympiads.

More information about NACLO, including a student handbook and practice problems, can be found at the official NACLO website, http://www.naclo.org.

How can I register for the Open (first) Round?

Students who are interested can register at the NACLO registration site.
Participation in the event is free.

IMPORTANT: Due to current Campus access restrictions, we are not able to accommodate same-day / walk-in registrations. Please ensure you are registered no later than Sunday, January 25th so we can arrange campus access for all participants.

Where is the Columbia University location for the Open (first) Round?

We will hold the NACLO Competition Open Round in room 414 on the fourth floor, Schapiro Center for Engineering and Physical Science Research (CEPSR), which is located at 530 West 120th St.

When should I arrive for the Open (first) Round?

The contest begins promptly at 10am and runs three hours until 1pm on Thursday, January 29, 2026. Please arrive on campus no later than 9:30am. Students who arrive late are not allowed to have extra time to have instructions/ announcements repeated for them.

Where is the Columbia University site for second (invitational) round?

To be announced.

When should I arrive for the second (invitational) round?

What should I study?

Some sample questions for practice are available here.
Columbia does not currently offer preparation workshops, but other local sites may offer events.

Who should I contact?

• Site host, main site contact: Dr. Daniel Bauer, <bauer [at] cs.columbia.edu>