The ideal carat weight for a Khooni Neelam depends on the preferences of the individual wearing it. Generally, a Khooni Neelam with a carat weight between 1-3 is preferred due to its affordability and good results in terms of colour and clarity. However, if budget is not a concern, higher carat weights can be chosen for greater intensity of colour and sparkles. Ultimately, the choice of carat weight lies with the wearer as per their preference.