Puzzles in undiscovered languages.

No prior knowledge required. Both competitions in this department give you a small fragment of an unfamiliar language — Tagalog, Hawaiian, Yoruba, Iatmul — and ask you to discover the grammar from scratch.

2 competitions 1 archived 1 in audit

In This Department

Two puzzles.

International Linguistics Olympiad

22 years · ~155 problems · 28 languages on file.

127 English-language problem PDFs (190 MB) downloaded and normalized. The flagship international olympiad of the field.

IOL · annual July →

Audit

Linguistics · N. American

NACLO

Round 1 (open) · Round 2 (invitational).

North America's IOL selection path. 2007–2025 problem and solution booklets publicly archived at naclo.org.

NACLO · January / March →

An editor's note

The cleanest entry test in this library.

If you've ever enjoyed a logic puzzle, you'll enjoy a linguistics olympiad problem. The format is the same everywhere — a small bilingual data set, a list of new words or sentences to translate, and the implicit instruction: work out the rule.

NACLO Round 1 is open to any North American school student and can be sat in March. The Round 2 invitational selects the US/Canada IOL teams. The IOL itself is held in a different country each summer; problems are translated into all participating national languages.

A free, structured study path

All NACLO and IOL problems and solutions are public. The Tian2 archive has 127 IOL English PDFs (2003–2025) downloaded and normalized.

— The Editors