Acidity of Prune Juice varies from 3.95 to 3.97

Acidity of Prune Juice is moderate - it is ok to consume it but in limited quantities.

Food Acidity ranges

For more details search on food acidity and alkalinity look at the list below. Items with higher values are the safest for your stomach. For more details on specific food items and whether they cause heartburn or not take a look at Food Database