Racks for test tubes have openings of various sizes to accommodate specific or a range of tube diameters, and securely hold tubes on benchtops, or in water baths, incubators, or refrigerators. Test tube racks have various configurations and can be stackable, have grips for inversion, be angled or have alphanumeric labels. Test tube rack shapes and sizes vary and they can be made from variety of materials, including plain or epoxy-coated metal, wood, foam, and various acrylics and plastics.