Ultrawide monitors start at around 34in, and this is the most common screen size for an ultrawide monitor, but there are plenty of ultrawide monitors that have even larger screen sizes, going up to a whopping 49 inches. While 34in is plenty big enough for most uses, a larger screen allows you to effectively replace a dual monitor setup retaining your screen real estate while tidying up your workspace in the process – you'll just need a large enough desk to accommodate it.