pH Calculator Formula

Understand the math behind the ph calculator. Each variable explained with a worked example.

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Formulas Used

pH

ph_value = -log10(h_conc)

pOH

poh_value = 14 - (-log10(h_conc))

Variables

VariableDescriptionDefault
h_concHydrogen Ion Concentration [H+](M)0.001

How It Works

How to Calculate pH

Formula

pH = -log10([H+])

pH ranges from 0 (very acidic) to 14 (very basic). pH 7 is neutral.

Worked Example

Find the pH of a solution with [H+] = 0.001 M.

h_conc = 0.001
  1. 01pH = -log10(0.001)
  2. 02pH = -log10(10^-3)
  3. 03pH = 3

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