Cooking times for slow cookers can be found on the Crock Pot website and at the Williams-Sonoma website, as of 2015. Taste of Home also offers a chart for converting conventional cooking times to comparable slow cooker times.
The Crock Pot site recommends cooking a 6-pound whole chicken for seven hours and 30 minutes on low or six hours and 15 minutes on high. The recommended cooking time for a beef roast weighing 3 to 4 pounds is eight hours on low or five hours and 45 minutes on high. To convert a conventional recipe that cooks for 15 to 30 minutes to the slow cooker, Taste of Home recommends cooking on low for four to six hours or on high for one hour and thirty minutes to two hours.