* No central registry: There is no single, universally recognized registry for all Arabian horses worldwide.
* Varying definitions: Different countries and organizations may have slightly different definitions of what constitutes an Arabian horse.
* Ongoing breeding: The number of Arabian horses is constantly changing due to breeding programs and other factors.
However, estimates suggest that the global Arabian horse population is somewhere between 1.5 and 2 million horses.
If you're interested in a more specific number, you could look at the populations registered with major Arabian horse organizations in different countries.