The world population is about 8.3 billion according to Worldometer. So when people ask “how many people have PhDs in the world?” a reasonable global ballpark is that ~0.1% to ~0.15% of the total world population holds a doctoral-level degree (PhD or equivalent). That gives:
- 8.3 billion × 0.1% = ~8.3 million
- 8.3 billion × 0.15% = ~12.5 million
✅ Closest practical answer: ~8 to ~12.5 million people worldwide hold a PhD / doctoral-level degree.
This is an estimate, not a census. There is no single global registry of living PhD holders, and “PhD” can be defined and reported differently across countries.
What “PhD” means in the data
For cross-country statistics, the cleanest comparable category is usually:
- Doctoral or equivalent degree (often aligned with ISCED 2011 level 8)
International datasets typically measure doctorate attainment as the share of adults whose highest qualification is doctoral/equivalent, rather than “PhD-only by name.” The World Bank also publishes a doctorate attainment indicator for adults 25+.
Based on the NCES/OECD international attainment table (Table 603.30) , the OECD average share of adults aged 25–64 whose highest qualification is a doctoral or equivalent degree is 1.3% (latest comparable year shown: 2022).
That is not the same measure as “percent of the entire world population with a PhD,” because:
- The OECD is not the world (it’s weighted toward higher-income, higher-attainment education systems).
- 25–64 is not all ages (whole-population shares include children/teens who almost never have doctorates).
- Rates vary sharply even inside the same table (for ages 25–64, Mexico is 0.1% while Switzerland is 3.2%).
PhD percentage by country (doctorate attainment, ages 25–64)
The table below is based on the NCES/OECD international attainment table (2022) and shows the share of adults aged 25–64 whose highest qualification is a Doctoral or equivalent degree.
| Country | % with doctorate (25–64) |
|---|---|
| Slovenia | 3.7% |
| Switzerland | 3.2% |
| Luxembourg | 2.9% |
| United States | 2.1% |
| Sweden | 2.0% |
| Germany | 1.9% |
| Australia | 1.9% |
| United Kingdom | 1.7% |
| Ireland | 1.7% |
| Denmark | 1.5% |
| Norway | 1.5% |
| OECD average | 1.3% |
| Finland | 1.3% |
| Netherlands | 1.2% |
| Austria | 1.2% |
| Belgium | 1.1% |
| New Zealand | 1.1% |
| France | 1.0% |
| Portugal | 0.9% |
| Spain | 0.8% |
| Czech Republic | 0.7% |
| Italy | 0.6% |
| Mexico | 0.1% |
Note: Some countries show missing values in this specific table (for example, Canada is not reported in the doctoral column here), so it’s better not to publish a number from this source when the cell is blank.
How rare is a PhD, really?
It depends on which population you mean.
In the whole world (all ages)
- 0.1% to 0.15% of 8.3B ≈ 8.3M to 12.5M people
- That’s roughly 1 in 1,000 to 1 in 667 people
(That’s exactly why a “whole population” share looks tiny: the denominator includes everyone, including children.)
In OECD countries (working-age adults 25–64)
- The OECD average is 1.3% (doctorate as highest degree), which is roughly ~1 in 77 adults (25–64).
- In some countries it’s much higher (e.g., Slovenia ~3.7% ≈ 1 in 27).
How many PhD students are there?
There isn’t one clean “worldwide” count published as a single number that covers every country the same way. But a high-quality regional benchmark exists for the EU.
In the EU
Based on Eurostat reporting for 2023:
- The EU had 18.8 million tertiary students
- 3.8% were studying for doctoral degrees
- That’s about 717,000 doctoral (or equivalent) students
Eurostat also highlights that Germany had a relatively high doctoral share (6.2%) and the largest doctoral-student count (205,300) in the EU.
How to interpret this: doctoral students are typically a single-digit percentage of tertiary students in most systems—so even in places with strong research universities, PhD students are a minority of the higher-education population.
How many PhDs are awarded each year?
Again, there is no perfect, single global annual total that works like a world census. But there are strong “anchor numbers” for major systems.
United States (research doctorates)
Based on the National Science Foundation’s Survey of Earned Doctorates, the number of research doctoral degrees awarded by U.S. institutions was 57,862 in 2023 (up from 57,448 in 2022).
OECD countries (new doctorates; older but useful for scale)
An OECD brief notes that new doctorates across OECD countries increased from 158,000 (2000) to 247,000 (2012), a rise of 56%.
Practical takeaway: annual PhD production is on the order of tens of thousands in large single countries and hundreds of thousands across major country groups—but the exact “world total” varies depending on which countries report, which doctorate types are included, and how “PhD-equivalent” credentials are counted.
Which countries have the most PhDs per capita?
If “per capita” means doctorate holders as a share of adults (25–64) using the comparable OECD/NCES table, the leaders in the list above are:
- Slovenia (3.7%)
- Switzerland (3.2%)
- Luxembourg (2.9%)
Who has the most PhDs?
There’s no single official global registry that ranks individuals by the number of earned PhDs/doctorates, so many “most PhDs” claims online are hard to verify consistently across countries and definitions.
One of the most consistently documented examples is Robert W. McGee, who is described by multiple institutional profiles as having earned 13 doctorate degrees:
- Gannon University alumni spotlight
- Cleveland State University Magazine feature
- American Institute for Economic Research bio
FAQ
How many people have PhDs in the world?
A closest practical estimate is ~8 to ~12.5 million people worldwide holding a doctoral-level degree (PhD or equivalent),
based on a world population of ~8.3B and a ~0.1%–0.15% global share estimate.
What is the OECD average percentage of doctorate holders?
In the comparable NCES/OECD table, the OECD average is 1.3% for ages 25–64 (doctorate as the highest degree).
The highest shares in the table are Slovenia (3.7%), Switzerland (3.2%), and Luxembourg (2.9%)
for ages 25–64 (doctorate as highest degree).
How many PhD students are there in the EU?
Eurostat reports approximately ~717,000 doctoral (or equivalent) students in the EU in 2023, and doctoral students
were 3.8% of tertiary students.
How many PhDs are awarded each year in the U.S.?
The U.S. National Science Foundation reports 57,862 research doctorates awarded in 2023 (up from 57,448 in 2022).
Who has the most PhDs?
There is no single official global registry of “most PhDs.” One of the best-supported public claims is that Robert W. McGee has
earned 13 doctorate degrees, based on multiple institutional profiles.
