The 11+ exam is not a national exam. The test is solely part of the selection process for secondary schools that select their pupils based on academic ability. National exams such as the GCSEs and A Levels are different in the sense that they are taken by all students in the country whereas the 11+ exam is only taken by students applying for selective schools.
Free interactive 11+ course access:
Also read our 11+ Exam Guide and FAQs for Parents