Hello aspirant,
The upper age limit for CDS IMA is 24 years. Since you are currently 21 years 3 months old, you have 2 years and 9 months left to appear for the CDS IMA exam. This means you can attempt the exam 3 more times before reaching the age limit.

However, please note that this is just a general estimate and the actual number of attempts may vary depending on the specific notification released by the UPSC for the CDS exam in 2025. It is always advisable to refer to the official notification for accurate information regarding the age limit and number of attempts allowed.

I hope this information helps you.