basic

pH Calculator

Convert between hydrogen-ion concentration and pH, and find pOH for the complementary side of the scale.

Daniel Oh By Daniel Oh
Reviewed by Dr. Helena Ortiz
Published Last reviewed 1 min read

Inputs

Results

Enter values and click Calculate to see results.
Was this helpful?

How to use this calculator

  1. Fill in the inputs above using the units you already have.
  2. Values update automatically as you type — no submit button needed.
  3. Hover any result row for the underlying formula and intermediate values.

Formula

pH = −log₁₀[H⁺], pOH = 14 − pH (at 25 °C).

In depth

Convert between hydrogen-ion concentration and pH, and find pOH for the complementary side of the scale.