pH and pOH Calculator
Calculate pH, pOH and [OH⁻] from the H⁺ concentration.
Enter the H⁺ concentration (mol/L); we will calculate pH, pOH and the acidity/basicity.
M
Result
pH 4
pH: 4 — Acidic
Result in all units
Step-by-step solution
pH = −log[H⁺]
What Is pH?
pH is the scale that shows the acidity or basicity level of a solution. It ranges from 0 to 14; 7 is neutral, below is acidic, above is basic.
How is it calculated?
How Is It Calculated?
pH = −log[H⁺]
- Enter the hydrogen ion concentration (mol/L).
For example, if [H⁺]=10⁻³, then pH = 3.
Frequently Asked Questions
By how much does acidity increase when pH drops by 1?
Because it is a logarithmic scale, when pH decreases by one unit the hydrogen ion concentration increases tenfold.