How frequently should I take full-length mock tests during UPSC preparation?

The frequency of full-length mock tests should evolve alongside your preparation, moving from periodic assessments to intensive exam simulations.
For Prelims, a target of 30 to 40 mocks is ideal. Begin taking one mock per week once you have covered roughly 70% of the syllabus. In the final three months, escalate this to two or three tests weekly. This transition helps shift your focus from content acquisition to mastering speed, accuracy, and elimination techniques.
For Mains, the focus is on writing endurance and time management. Post-Prelims, aim for 10 to 15 full-length mocks. Initially, take one every fortnight, increasing the frequency to once a week as the exam nears. Occasionally, simulate the actual UPSC schedule by writing two tests in a single day to build the necessary mental and physical stamina.
The most critical factor is the analysis phase. You must spend at least three hours reviewing each mock to understand your mistakes. Taking fewer tests with deep analysis is far more beneficial than taking many without identifying your weak spots.