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 Cis-aconitic Acid
Chemical formula: C6H6O6
Cis-aconitic Acid is Acidic
At concentration of 1 mM, it has a pH of 3.05
At concentration of 10 mM, it has a pH of 2.21
At concentration of 100 mM, it has a pH of 1.55