If you need a double bathroom vanity for an average sized master bathroom, you want to be shopping in the 50-70 inch bracket. For a comfortable amount of space (both storage and standing) for two, you probably don´t want anything smaller than a 60" vanity, but double bathroom vanities as small as 52" are available if you´re in a really tight space and can´t stand to share a sink. For those with bigger bathrooms, this is also the size bracket where you´ll find the largest single vanities available - typically in the 56" - 60" range.
