From the UNESCO Institute for Statistics (UIS).
From an Introductory Blog Post
What is the UIS Learning Assessments Database and where can you find it?
The database is a free online resource available at this link, which provides standardised information on public examinations and national learning assessments conducted around the world.
Users can access the Database to search for or browse information on examinations and assessments according to different criteria, such as the subjects assessed or the source of funding. Once users have identified particular examinations or assessments of interest, they can access further details about each one through the associated UIS Catalogue of Learning Assessments, also a free open access resource at this link.
Read the Complete Introductory Blog Post
Direct to Database of Learning Assessments
Direct to UIS Catalogue of Learning Assessments