pH Calculator

pH Calculator is a free online tool to display the pH value of any chemical solution. Protonstalk pH calculator is one such tool to display the pH value faster and easier.

About pH Calculator


Following are the inputs of the calculator

  1. To Calculate (pH or pOH)
  2. Concentration
  3. Unit of Concentration (M, mM, uM, nM)
  4. Chemical Name/Formula

Example Input:
1. pOH
2. 1
3. M
4. NaOH

Steps To Use

Step 1: Enter the inputs.
Step 2: Click on the “Calculate” button.
Step 3: The result displays in a new window.


Following are the outputs of the calculator

  1. Input interpretation
  2. Result
  3. Acid-base information (pH, pOH, [H3O+], [OH], % ionization)

What is pH?

The pH value of any solution is the concentration of \(H^{+}\) ions in it. pH is a measurement to determine the acidity or alkalinity of a solution. A pH scale ranges from 0 to 14.

Acidic solutions have a pH less than 7 as they have higher concentrations of \(H^{+}\) ions. Basic solution with lesser \(H^{+}\) ions concentrations have a pH greater than 7. Solutions with pH value 7 are neutral solutions such as pure water.

pH values of solutions are determined at room temperature i.e \(25^{\circ}\)C as pH changes with temperature as well.


To calculate pH, we use a formula pH=\(-log_{10}[H^{+}]\)

Consider \([H^{+}]\) = \(1.4 \times 10^{-5}\) then its pH value would be

pH = \(-log_{10}[H^{+}]\)
pH = \(-log_{10}[1.4 \times 10^{-5}]\)
=> pH = 4.85

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