Some online resources that allow you to test your own vision include Essilor and Enchroma. Both of these resources provide a variety of online tests to check different areas of vision for free.
Essilor has multiple vision tests, including for far vision, near vision, myopia, ishihara and astigmatism. The astigmatism vision test looks at issues with not being able to drive at night or having issues seeing certain letters. The near and far vision tests use letters of different sizes to determine how many can be easily seen while covering one eye. The myopia test looks to see if the person sees better in a certain color range.
Enchroma only checks for color blindness, measuring the type of color blindness someone has and its approximate extent.