A:Answer The short answer is allot. The long answer is it depends on which format you're shooting. IE: jpeg, tiff, raw, video etc..I guess you could say size matters. As an amateur I don't take the number of photos that a pro will and I don't need to preserve everything. I shoot in Nikon's NEF format which are large files and I still have plenty of space on my drive. If I fill it up I won't have any issues adding another one of these to my collection because it's fast and fits my needs perfectly.