pH Calculator
The pH and pOH from the hydrogen ion concentration.
Result
pH
4.00
pOH
10.00
How it works
pH = −log₁₀[H⁺], pOH = 14 − pH
pH measures acidity on a 0–14 scale. It is the negative base-10 logarithm of the hydrogen ion concentration; 7 is neutral, lower is acidic, higher is basic.
Advertisement
Frequently asked questions
What is a neutral pH?
7 at 25 °C, where [H⁺] = 1 × 10⁻⁷ mol/L.
What is pOH?
The hydroxide counterpart; at 25 °C pH + pOH always equals 14.
Advertisement