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Which Countries Have the Most University Graduates?

Which countries have the highest share of university graduates, and how do major economies compare?

This graphic ranks 43 countries by the estimated share of adults aged 25–64 who have attained at least a bachelor’s degree, revealing some surprising leaders.

The data come from the OECD’s Education at a Glance 2026, with 2020 figures for China taken from Education at a Glance 2022. Estimates combine the reported shares holding bachelor’s, master’s, and doctoral or equivalent qualifications; short-cycle tertiary programs are excluded.

Most figures are from 2025, while Chile uses 2024 data and Iceland and Indonesia use 2023 data.

Europe Dominates the Top of the Ranking

Across the OECD, 43% of adults aged 25–64 held some form of tertiary qualification in 2025. The OECD average for bachelor’s degrees or higher was roughly 35%.

Ireland sits comfortably in first place, seven percentage points ahead of Lithuania at 50%. Luxembourg follows at 48%, while Belgium, Switzerland, and the United Kingdom are tied at 46%, giving European countries all six leading positions.

Australia and South Korea are the only non-European countries in the top 10, both at 43%.

Yet Europe is far from uniform. Italy and Austria are at 22%, while Romania stands at just 19%, highlighting the wide differences in degree attainment across the region.

Why Ireland Leads in University Degree Attainment

Ireland’s leading position reflects decades of policies aimed at expanding access to higher education. The introduction of tuition-free undergraduate education in the 1990s, student grants, and the expansion of regional universities have helped increase participation.

Strong demand for skilled workers in the technology and pharmaceutical industries has also supported higher education.

Ireland also attracts highly educated international workers. In 2025, 67% of non-Irish nationals held a third-level qualification, compared with 56% of Irish nationals. This broader measure includes qualifications beyond those counted in the ranking.

North America and Asia Show Different Patterns

Canada’s position may surprise readers familiar with rankings that place it among the world’s most educated countries. While 39% of Canadian adults hold a bachelor’s degree or higher, the country also has a large share of people with shorter postsecondary qualifications.

According to the OECD, 25% of Canadian adults have a short-cycle tertiary qualification as their highest level of education. Because these qualifications are excluded from this ranking, Canada places below the United States at 41%.

In Asia, South Korea leads the countries shown at 43%, followed by Israel at 40% and Japan at 37%. Türkiye is further down the ranking at 20%.

What the Lowest Shares Tell Us

At the other end of the ranking, South Africa stands at 8%, China at 9%, and Indonesia at 10%, far below the leaders in this dataset.

However, China’s figure is from 2020 and Indonesia’s from 2023, so these percentages should not be treated as a single-year snapshot of global attainment.

Education systems also differ in their emphasis on apprenticeships, technical qualifications, and short-cycle tertiary programs, which are not necessarily captured by this degree-focused measure.

Degree attainment is useful for comparing formal qualifications, but it cannot on its own establish the quality of education, the skills workers possess, or the opportunities available to graduates.

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If you enjoyed today’s post, check out Ranked: Where Public University Tuition Is Most Expensive on Voronoi.

Which Airports Are the Busiest in North America?

More than 100 million passengers passed through Atlanta’s Hartsfield-Jackson airport in 2025, keeping it firmly atop the global rankings.

This graphic ranks North America’s 10 busiest airports by total passenger traffic, using 2025 figures from Airports Council International. Totals include arriving and departing passengers on both domestic and international flights.

Atlanta: The Airport Capital of America

Hartsfield-Jackson Atlanta handled 106.3 million passengers in 2025, compared with 85.7 million at runner-up Dallas Fort Worth. That gap of approximately 20.6 million passengers translates to more than 56,000 additional passenger movements per day.

Below Atlanta, the competition was considerably tighter. Dallas Fort Worth finished just 804,000 passengers ahead of third-place Chicago O’Hare (84.9 million), while Denver (82.4 million) followed close behind.

Atlanta’s dominance stretches back decades. Hartsfield-Jackson has held the title of world’s busiest airport by passenger traffic every year since 1998 except 2020, when the pandemic disrupted global travel.

Despite covering three major aviation markets, the entire top 10 consists of U.S. airports. Canada’s busiest, Toronto Pearson, handled 47.2 million passengers in 2025, placing it below San Francisco, the 10th-ranked airport, at 54.5 million.

The Hub and Spoke Strategy

The top three airports in North America are major hubs for the Big Three U.S. network airlines. Atlanta is Delta’s largest hub, while Dallas Fort Worth serves as American Airlines’ largest hub and Chicago O’Hare is a major United Airlines hub.

Atlanta benefits from geography as well as airline scale: approximately 80% of the U.S. population is within a two-hour flight. That makes it a useful transfer point for travelers connecting between cities across the country and abroad.

Concentrating flights at one airport allows airlines to combine passengers from many origins onto connecting services. By May 2026, Delta offered nearly 1,000 peak-day departures from Atlanta to 207 destinations. That extensive network helps explain why Atlanta handles so many passengers whose journeys begin and end elsewhere.

Chicago’s Gains and the Vegas Slump

Chicago O’Hare and Las Vegas recorded sharply different results in 2025. O’Hare’s passenger traffic rose 6%, the fastest growth among North America’s 10 busiest airports, while Harry Reid International in Las Vegas experienced the largest decline at 5.9%.

O’Hare’s growth also outpaced the 3.7% increase in global passenger traffic. The Chicago airport ranked first worldwide for aircraft movements, or takeoffs and landings, even as Atlanta retained its lead in total passengers.

Las Vegas handled approximately 55 million passengers amid a broader tourism slowdown. The city welcomed 38.5 million visitors in 2025, down 7.5% from the previous year, while hotel occupancy and average room rates also declined.

Convention attendance remained comparatively steady at approximately 6 million, helping support Las Vegas as leisure and international visitation weakened.

Learn More on the Voronoi App

To compare North America’s busiest airports with those across the Atlantic, check out The top 10 airports in the EU based on number of flights on Voronoi.