Basins tend to vary between 22 and 25 inches in width; this can affect how wide the ledges are on either side, as well as which trays will fit inside your tub. We primarily tested trays with a smaller-than-average tub that was 28 inches wide from wall to outer edge, with a 22-inch basin. The ledge on either side of this tub, where the trays rest, was about 3 inches wide. (You can see a photo of the tub we tested in below. We shot the rest of the photographs for this guide with a different tub, noting its dimensions in the discussion of each pick.) We know that a lot of tubs barely even have a ledge on the wall side, though, which might mean that a bath tray will not work for you, no matter how wide your tub is. While you measure, be sure to check for any other features in your tub that could get in the way. For example, my own tub, pictured below, has a grab bar molded into the inner wall, which means I can place bath trays only on either side of that handle.
