Unopened cans of paint can last for around three years, so long as it’s stored properly. Once your paint has been opened, shelf life can vary depending on factors like temperature and air exposure. If the paint is exposed to too much air, it can potentially dry out. Sealing your paint tightly will keep your paint fresh for as long as possible. Seal your paint can tightly using a rubber mallet (not a hammer, which can leave dents in the can) so air doesn’t seep in and shorten the paint’s shelf life. Room temperature is ideal and you should avoid extreme hot or cold temperatures which can ruin your paint.