How to set the ring
Enter one positive number per slice, the same way you would for a pie. The slices are shares of the total of those numbers. If a category is not part of that total, it does not belong on this chart. A doughnut does not become more honest by looking modern. It has the same limit as a pie: people compare angles poorly when the slices are many and similar. Keep the list short, and put the small remainder in Other.
The hole size is a slider. A small hole looks almost like a pie. A large hole makes a thin ring, which is elegant until the slices become hard to tell apart. Leave enough ring that a colored band is obvious at arm’s length. The start angle rotates where the first slice begins. Use it to park a thin slice where the legend, not the ring, carries the name.
Turn on percentages when the story is share. Turn on value labels when the story is the count. You rarely need both on a thin ring, because the text will not fit inside a narrow band. The legend lists every slice with its percentage, so the ring itself can stay quiet. Colors should differ between neighbors. A palette of similar blues will collapse when the page is printed or projected.
The title names the whole. The subtitle can name the period or the rule, such as March household budget or share of open tickets. Do not repeat the slice names in the subtitle. Sort by value for a ranked share. Leave the weekday or process order alone when sequence matters more than size.
Export PDF if the ring is going onto paper, PNG if it is going onto a page where text must stay crisp, and JPEG if a photo file is required. The chart is stored in this browser only. From the tool grid you can switch to the pie chart if you decide the hole is wasting the part of the picture people need, or to a stacked bar if the whole is better read as a stack of lengths than as a ring.