Is vinegar 100% acetic acid?

Is vinegar really just pure acid?

When you reach for a bottle of vinegar to season a salad or clean a countertop, you are actually holding a very diluted solution. Far from being a harsh, 100% acid, standard culinary vinegar is typically only about 4% to 6% acetic acid dissolved in water, with the rest made up of water and trace flavor compounds from its fermentation source.

If you were to encounter 100% acetic acid, it certainly wouldn't belong in the kitchen. In laboratory and industrial settings, much higher concentrations are handled with strict safety precautions. Pure or near-pure acetic acid—containing only minimal traces of water—is known as glacial acetic acid. It earned this chilly name because it freezes into ice-like crystals just below room temperature, at around 16.6°C (62°F).

So, while that sharp tang in your pantry definitely comes from acetic acid, it is heavily watered down, making it safe, mild, and endlessly useful for everyday cooking and household tasks.