pH Calculator for Strong and Weak Acids

pH Calculator for Acids

Calculate the pH for either a strong acid or a weak (monoprotic) acid.

* Enter the acid concentration (in mol/L). For a weak acid, also enter its pKₐ.

Step 1: Enter Acid Parameters

Example: 0.1 M

For Strong Acids: \( \text{pH} = -\log_{10}(C) \)
For Weak Acids: Solve \( x^2 + K_a\, x – K_a\, C = 0 \) for \( x \) then \( \text{pH} = -\log_{10}(x) \) (with \( K_a = 10^{-\text{p}K_a} \)).