When using vanilla extract, a little goes a long way, so it's possible to keep one bottle in your cupboard for years. However, many of us may wonder if it's actually safe to use extract that's years old, or if there is a certain timeframe in which you should use up your bottle before it's past its prime.

As long as you follow the storage instructions on the bottle, your vanilla extract can, in fact, stay good and usable for years, even after opening. There isn't a set window for just how long your extract will keep, though as it gets older, the alcohol content will evaporate, resulting in a stronger taste of vanilla.

A bottle of pure vanilla extract can last around a decade, while a synthetic extract can last as long as four years. A decrease in quality and aroma is typically the only side effect of a synthetic extract "going bad," so try smelling the bottle if you suspect it's too old, but pure extract is unlikely to ever go "off" at all.