What is the percentage of acetic acid in vinegar?

In general, manufacturers dilute the acetic acid in vinegar to the 5 percent to 10 percent level. The amount varies based on the dilution by the manufacturer.

Heinz dilutes all of its vinegars to 5 percent acetic acid, with the exception of a cleaning vinegar that contains 6 percent acetic acid. The manufacturer produces vinegar by allowing alcohol to ferment a second time to produce acetic acid. It uses grain alcohol in production of distilled white vinegar, while apple cider or wine is common in other types of vinegar. It produces malt vinegar by allowing beer to ferment a second time.