This little website shows you the pH of various acids, bases, food products, bodily fluids, cleaners, and more!
Here's a random substance:
pH of Methylsuccinic Acid
Chemical formula: C5H8O4
Methylsuccinic Acid is Acidic
At concentration of 1 mM, it has a pH of 3.62
At concentration of 10 mM, it has a pH of 3.08
At concentration of 100 mM, it has a pH of 2.57