Ultimate Guide to the International Biology Olympiad in

The International Biology Olympiad (IBO) is the world's leading biology competition for high school students, held each year in a different host country. The competitors are the very best young biologists on the planet, each selected through their country's national biology olympiad, and an IBO medal is among the rarest and most respected credentials in all of student science.

The 37th IBO took place in Vilnius, Lithuania, from July 12 to 19, 2026, bringing together around 300 students from 78 countries. This guide covers who can compete, how qualification works, what the exams look like, and how to prepare, whether you are aiming to represent your country or simply want to challenge yourself against the hardest biology problems in the world.

What Is the IBO?

The IBO began in 1989 with six participating nations and has grown into one of the five major international science olympiads. Each participating country sends a team of up to four students, selected through its national biology olympiad, along with team leaders and mentors.

At IBO 2026, a total of 185 medals were awarded across gold, silver, and bronze, and the United States was among the strongest teams in the field, with all four American students earning gold medals.

Upcoming editions are already scheduled, with the 38th IBO in Warsaw, Poland, from July 18 to 25, 2027, followed by the Netherlands in 2028 and the Czech Republic in 2029.

Eligibility and How Qualification Works

You cannot enter the IBO directly. Every competitor qualifies by winning a place on their national team, and the eligibility rules are set internationally: you must be a secondary school student, you must be selected through your country's national biology olympiad, and each country may send at most four students.

This guide describes the qualification pathway in the United States. If you are competing from another country, check your national biology olympiad's rules, since the selection process, deadlines, and exam structure vary by nation.

The US Pathway: From USABO to the IBO

In the United States, the road to the IBO runs through the USA Biology Olympiad (USABO), administered by the Center for Excellence in Education. Nearly 12,000 students register each year, and the competition narrows the field across three rounds before the national team is selected.

The Open Exam in February is open to all US students in grades 9 through 12 registered through their schools. The top 600 scorers nationwide advance to the Semifinal Exam, where the difficulty rises sharply with analytical, data-driven questions. The top 20 Semifinalists are then invited to the National Finals, a residential training program combining advanced theoretical study with exacting laboratory work, and the four gold medalists from Finals earn the right to represent the United States at the IBO.

Registration for the USABO runs through your school in the fall, months before the February Open Exam, so the first practical step toward the IBO is making sure your school registers on time. We cover the American competition in full detail, including round-by-round strategy, in our ultimate guide to the USA Biology Olympiad.

The IBO Exam Format

The IBO consists of two components carrying roughly equal weight, held on separate days.

The theoretical exams test problem-solving across the full breadth of biology, from cell biology and biochemistry to physiology, ecology, ethology, and evolution.

The practical exams place students at the lab bench, where they carry out real experiments and analyze results under time pressure. Both components are long, demanding sessions, and success requires genuine laboratory competence alongside deep conceptual knowledge.

That practical component is what most distinguishes the IBO from exam-only competitions. National teams typically receive intensive training in advanced laboratory techniques before the competition, covering skills like dissection, microscopy, molecular biology methods, and statistical analysis of experimental data that go well beyond any high school curriculum.

How to Prepare

For most students, preparing for the IBO means preparing to dominate your national olympiad first, and the foundations are the same everywhere. Master a university-level general biology text like Campbell Biology thoroughly, then go deeper in the areas your national exam emphasizes. Work through past exams systematically under timed conditions, including the IBO's own past papers, which are published openly on the official IBO website and are the single best preview of international-level difficulty.

Laboratory experience is the piece most students under-invest in. Seek hands-on bench time early through school labs, local universities, or biology summer research programs, and learn core techniques like PCR, gel electrophoresis, and microscopy alongside the theory behind them. By the time practical skills decide who makes the national team, they are very hard to build quickly.

Finally, remember that the IBO is the summit of a large mountain range. If you are building a biology profile, our ultimate list of biology competitions for high school students maps the many competitions worth considering alongside or before an olympiad campaign.

From Olympiad Biology to Original Research

The IBO measures how deeply you understand biology that is already known. Original research asks the complementary question: can you discover something new? Many of the strongest olympiad competitors eventually take that step, building research projects that compete at science fairs like the Regeneron International Science and Engineering Fair (ISEF), the world's largest pre-college STEM research competition, or at research-based competitions like the GENIUS Olympiad.

Interested in Biology Research?

We do not coach for olympiads, but if you want to turn your biology knowledge into an original research project, our coaches include ISEF Grand Awardees and Regeneron STS Scholars who have built award-winning research of their own. Book a free consultation to talk with an academic advisor about what a research project could look like for you.