A great way to determine the minimum weight for your umbrella stand is to multiply the width of your umbrella canopy by 10. For example, for a 7.5' umbrella we recommend using a 75 lb. umbrella stand; a 9' umbrella will require at least an 90 lb. umbrella stand. Keep in mind that the weight recommendation is a minimum guideline, and you may want to use a heavier base if you live in a windy area or plan to use your umbrella in unstable ground conditions. Additionally, you can use sandbags or other weights to supplement the base weight and increase stability.