Upvote:4
Indian citizens don't need an Airport Transit Visa (ATV) for Belgium. There are four countries in the Schengen region which require ATV from Indian citizens. They are France, Germany, Spain and Czech Republic.
You can find information on the websites of the individual Schengen countries. Belgium's website refers to the general EU website which has published a "table" in this regard. Here is the link to that:
https://home-affairs.ec.europa.eu/system/files/2022-09/Annex%207B.pdf