This doesn't seem a very spiritual question: How heavy are you? Neither may these: What is your size? What is your age? These all seems like questions it can be considered rude to ask. But explore them from a spiritual angle, not a personal one, and they can point to the true nature of our being.
Weight, size and age are relative to the human perspective in the human world. But look deeper to who you are. Look to where you are looking from. I don't mean the eyes. We experience seeing, yes. We perceive other senses as well: hearing, taste, touch, smell, balance etc. We experience these senses from a central point. In the Non Dual understanding we are Awareness itself, that unchanging state wherein all change is perceived. Let's look there. Or rather, let's look Here. It is the closest point of being you. Closer than the arms and legs. Closer than the eyes and ears. Closer than thoughts even. Let's look here, where even thoughts are perceived.
How heavy are you here? There is no weight. What is your size here? There is no size. What is your age here? There is no age. The real you is formless intelligent awareness. You are as you are. There is no ageing here, no being born or dying. There is no time or space. Just formless awareness perceiving the play of time and space. Being formless, you have no depth or change. You cannot be weighed down. You are neither large nor small. We could say your size is infinite, but even the concept of infinity is not accurate enough, as you have no size.
No qualities stick to you. You are perfect, in that you have no faults. Perfect from the human perspective, but just as you are in truth. You have no lack or need. In that sense you are complete, but beyond the concepts of complete and incomplete. These are human concepts, similar to weight, size and age.
Being formless you are not limited by the appearance of the world, by descriptions about you, or by the appearance of forms that are perceived. Here you are, the basic component of all life. That which is. That without which the world does not appear. You are I Am, the basic quality of being, without attachment or identity. There is no attachment or identity because there are no limits to divide you and separate you from something else. There is no something else. You are as you are. I am that I am.