How long to balloons hold air?

Balloons can hold air for varying lengths of time depending on their material and environmental conditions. Latex balloons typically last around 8 to 12 hours when filled with air, while mylar (foil) balloons can hold air for several days or even weeks. Factors such as temperature, humidity, and the size of the balloon also influence how long they retain air. Over time, air will slowly seep through the balloon's material, causing it to deflate.