Is it possible for nearsightedness to make you blind?

Very rarely: People who are very nearsighted (-6 diopters or greater) should avoid lifting heavy weights because this may cause retinal detachment (and that can cause floaters/vision loss). Nearsightedness may get worse over time, but it is unlikely to transition into blindness unless another underlying eye disease is present, such as glaucoma (increased pressure in the eye), cataracts, or macular degeneration.